Why do scientists use models?
A)
Models are unreliable.
B)
Models waste natural resources.
Models predict not just describe events.
Models are based on scientific laws and principals so they are more
reliable than the real thing.
D)

Answers

Answer 1
The correct answer is A

Related Questions

Help me little brother with his math please

Answers

Answer: less,less greater

Step-by-step explanation:

Answer: #1 : less than 930

Answer: #2 : less than 930

Answer: #3 : greater than 930

Hope this helps older sis!

Divide 2+1/2
A. 2
B. 16
C. 8
D. 4

Answers

4 because i know it is

Answer:

the answer would be 4, the number 2 would double since your dividing it by 0.5

can someone help me with the equation(s)

Answers

She purchased 8 sports drinks

{d=p+3

2.25p+1.25d=21.25

d=p+3

p=d - 3

2.25(d - 3) + 1.25d = 21.25

2.25(d-3) + 1.25d=21.25

2.25 - 6.75 + 1.25d = 21.25

3.5d = 21.25+6.75

d=28/3.5

D=8

When we solve the inequality, will we keep or switch the inequality sign?

−2x>13


Keep

Switch

Answers

Answer:

switch I think cuz there is a negative

Step-by-step explanation:

Hope u have a nice day

Answer:

switch

Step-by-step explanation:

whenever u divide a number by a negative number across the inequality, the inequality sign switches

17/6 + 4/3 fractions

Answers

Answer:

25/6

Step-by-step explanation:

I multiplied 4/3 by 2, so the new fraction is 8/6. You add 17/6 with 8/6, and you get 25/6. I hope you understand.

Write 3 9/10 as an improper fraction.

Answers

Answer:

39/10

Step-by-step explanation:

Answer:

39/10

Step-by-step explanation:

to make 3 9/10 an improper fraction all you have to do is take the whole number-3 and take the denominator-10 and multiply them 3 x 10 = 30, then add it to the numerator 9 + 30 equals 39 this is your new numerator

Solve the system of linear equations by substitution.
1/2x +y=-4
y = 2x + 16

Answers

sub 2x+16 for y into the 1st line so
1/2x+2x+16=-4 now find x
which is x=8 not plug in -8 for x, does not matter which one
you will get y=0
answer•
x=-8
y=0
(-8,0)

Answer:

y = 0

x = -8

Step-by-step explanation:

1/2x + y = - 4

y = 2x + 16

1/2x + (2x + 16) = - 4

1/2x + 2x = - 4 - 16

5/2x = -20

2/5 x 5/2x = -20 x 2/5

x = -40/5

x = -8

y = 2x + 16

y = 2(-8) + 16

y = -16 + 16

y = 0

Check:

1/2x + y = - 4

y = 2x + 16

1/2(-8) + (0) = -4

-4 + 0 = -4

-4 = -4

y = 2x + 16

(0) = 2(-8) + 16

0 = -16 + 16

0 = 0

Bianca set the thermostat in her house to 87°F, which was 13° warmer than the temperature outside. What temperature was it outside?

Confused.

Answers

Answer: 74 degrees Fahrenheit  

Step-by-step explanation: the temperature outside was 13 degrees lower than 87 degrees, so  87 - 13 = 74

Answer:

74 degrees F

Step-by-step explanation:

Subtract the 87 - 13

This is because there are +13 degrees more than outside. So if you add 74 + 13 that were added by the thermostat, you get 87 degrees. Does it make sense?

Just subtract :)

What is the common factors of 9 and 67



Please don't google it

Answers

Answer:

1

Step-by-step explanation:

Answer:

1

Step-by-step explanation:

9 1, 3 9

67 1 and 67

so just enjoy ur day and have a great Christmas and new year

Each of the numbers 0, 2, 4, 6, 8, 10, 12, and 14 is written on a separate sheet of paper and placed into a box. One piece of paper is selected at random. Find the probability that the piece of paper selected contains the number 8 or a number less than 12.

Answers

Answer:

For the second, all numbers less than 12, that would be 87.5%

Step-by-step explanation:

There are eight numbers. 100 divided by 8 is 12.5. 12.5 multiplied by 7 is 87.5.

Factorize;Answer the tick one i will mark you as brainlist please quickly step by step explanation also please show it clearly i will mark you as brainlist​

Answers

Answer:

Solved only ticked ones

4a² + 49b² = (2a + 7b)² - 28ab = 11² - 28*2 = 654x² + 9y² = (2x + 3y)² - 12xy = 12² - 12*6 = 724x² + 9y² = (2x - 3y)² + 12xy = 2² + 12*8 = 10016x² + 25y² = (4x - 5y)² + 40xy = 6² + 40*8 = 356

Answer:

use the formula:

[tex]a {}^{2} + {b}^{2} = (a + b) {}^{2} - 2ab[/tex]

1) 4a² + 49b²

= 2²a² + 7²b²

= (2a)² + (7b)²

based on the formula above, a = 2a and b = 7b

= ( 2a + 7b )² - 2(2a)(7b)

substitute 2a+7b = 11 into the equation

= 11² - 2( 14ab )

= 121 - 28ab

substitute ab = 2 into the equation

= 121 - 28(2)

= 121 - 56

= 65

2) 4x² + 9y²

= 2²x² + 3²y²

= (2x)² + (3y)²

based on the formula, a = 2x and b = 3y

= ( 2x + 3y )² - 2(2x)(3y)

substitute 2x+3y = 12 into the equation

= 12² - 2(2x)(3y)

= 144 -2(6xy)

= 144 - 12xy

substitute xy = 6 into the equation

= 144 - 12(6)

= 144 - 72

= 72

3) 4x² + 9y²

= 2²x² + 3²y²

= (2x)² + (3y)²

= (2x)² - (-3y)²

based on the formula, a=2x and b=-3y

= ( 2x-3y )²- 2(2x)(-3y)

substitute 2x-3y = 2 into the equation

= (2)² - 2(2x)(-3y)

= 4 - 2( -6xy )

= 4 + 12xy

substitute xy = 8 into the equation

= 4 + 12(8)

= 4 + 96

= 100

4) 16x² + 25y²

= 4²x² + 5²y²

= (4x)² + (5y)²

= (4x)² - (-5y)²

based on the formula, a = 4x and b = -5y

= (4x-5y)² - 2(4x)(-5y)

substitute 4x-5y = 6

= (6)² -2(4x)(-5y)

= 36 -2(-20xy)

= 36 + 40xy

substitute xy = 8 into the equation

= 36 + 40(8)

= 36 + 320

= 356

a sandbox is in the shape of a right triangle. The two legs measure 9 inches and 16 inches. what is the perimeter of the sandbox?​

Answers

Answer:

Perimeter = 50 inches

Step-by-step explanation:

Use pythagoreon theorem to find the hypotenuse

a^2 + b^2 = c^2

3^2 + 4^2 = 5^2

9 + 16 + 25 = perimeter

perimeter = 50

A statistics teacher announces to the class at the beginning of the semester that there is a 40% chance that a randomly chosen student will finish the semester with an A in the class and there is a 60% that a randomly chosen student will get an A on a test during the semester. Is the probability that a randomly chosen student receives an A in the class and an A on a test during the semester equal to 0.24? Yes, because the chance of getting an A on a test and getting an A in the class are mutually exclusive. Yes, because the chance of getting an A on a test and getting an A in the class are mutually exclusive. No, because the chance of getting an A on a test and getting an A in the class are not independent. No, because the chance of getting an A on a test and getting an A in the class are not independent. Yes, because the chance of getting an A on a test and getting an A in the class are independent. Yes, because the chance of getting an A on a test and getting an A in the class are independent. No, because the chance of getting an A on a test and getting an A in the class are not mutually exclusive.

Answers

Answer:

c. No, because the chance of getting an A on a test and getting an A in the class are not independent.

Step-by-step explanation:

brainly?

A new pair of boots is priced at $123.75, plus 6% sales tax. What is the total cost of the boots?

Answers

Answer:

131.18

Step-by-step explanation:

lemma get some help plz

Answers

Answer:

-2.6f -16

Step-by-step explanation:

add like terms -

-2.6 + 0.3 = -2.6f

and

-12-4 = -16

ahhhh I need help please!!

Answers

Answer:

two teaspoons i think sorry if this doesnt help

Step-by-step explanation:

What are the coefficients and constants of 7+5x need fast!!!!

Answers

Answer:

35

Step-by-step explanation:

there u go have a great day!

Answer!
A car travels from A to B at a speed of 30 mph then returns, using the same road, from B to A at a speed of 65 mph. What is the average speed for the round trip?

Answers

Here is an example for your question



Average with respect to what? If we take the time-weighted average, the two legs of the trip will be weighted differently (the leg from A to B taking 60/40 = 3/2 times as long as the leg from B to A), and we will get an average of 48 MPH.

But the time-weighted average is not the only average we can consider. We could also consider the distance-weighted average (which might be useful if we were considering, say, the wear on the road caused by such travel); then the two legs would be weighted equally and the average would be 50 MPH.

Often, when people speak about average speed, it's the former of these notions which is implicitly meant (since speed itself is distance over time, we have the nice property that the time-weighted average of speeds will always be the total distance over the total time), but the latter is a perfectly legitimate notion as well. Averages are always averages with respect to some weighting, and different weightings will give different averages.

Answer:

         41 mph

Step-by-step explanation:

s₁ = s₂ = x       {the distance from A to B}

s = s₁ + s₂ = x + x = 2x      {the distance of the round trip}

t = t₁ + t₂               {the time of the round trip}

v₁ = 30 mph      

v₂ = 65 mph

t₁ = s₁/v₁ = x/30 h       {the time of trip from A to B}

t₂ = s₂/v₂ = x/65 h      {the time of trip from B to A}

The average speed:

[tex]v=\dfrac st=\dfrac{2x}{\frac x{30}+\frac x {65}}=\dfrac{2x}{x(\frac 1{30}+\frac1 {65})}=\dfrac{2}{\frac{13}{390}+\frac6{390}}=2\cdot\frac{390}{19}=41.05263...\approx41[/tex]

If Z= 2+2i, what is z^4?

Answers

Answer:

D. 64 (cos(pi)+isin(pi))

Step-by-step explanation:

Put 2+2i into trigonometric form, raise the r value to the power of 4, and multiply the angle value (theta) by 4 to get the equation of z^4. In this case, r was 2(sqrt2), which raised to the 4th power was 64. The angle value was pi/4, which multiplied by 4 was pi. That's how we get the answer:

64 (cos(pi)+isin(pi)). How this helps!

Following are the calculation to the given value:

Given:

[tex]\to Z= 2+2i[/tex]

To find:

[tex]Z^4=?[/tex]

Solution:

[tex]\to Z= 2+2i[/tex]

[tex]\therefore\\\\i^2= -1[/tex]

[tex](a+b)^2= a^2+b^2+2ab[/tex]

Square the given value:

[tex]\to Z^2= (2+2i)^2[/tex]

         [tex]= 2^2+(2i)^2+2 \times 2 \times 2i\\\\= 4+4i^2+8i\\\\= 4-4+8i\\\\=8i[/tex]

When [tex]Z^2= 8i[/tex] then again square the value

[tex]\to ( Z^2)^2= (8i)^2\\\\\to Z^4= 64i^2\\\\\to Z^4= -64\\\\[/tex]

Therefore, the final answer is "-64".

Learn more:

brainly.com/question/25250313

Question 22 of 25
Which of the following are solutions to the quadratic equation below?
Check all that apply.
3x2 - 7x-3 = x
D A. 1
B. 3
] j
C. -3
D. -4
E.
=
1
O F..2

Answers

B and E. see attached

Plz answer these 2 I’ll mark brainliest

Answers

Answer:

16. C

17. B

sorry if i got it wrong

Answer:

THE ANSWER

A

B

Step-by-step explanation:

MARK BRAINLIEST

Collin is playing a video game. He wins 25 points for each gold coin he finds. His goal is to win more than 200 points. He wants to know how many gold coins he needs to find.

Answers

Answer:

200/25×1

=8 gold coins

Step-by-step explanation:

The required number of gold coins he needs is given 8 coins.

Given that,
Collin is playing a video game. He wins 25 points for each gold coin he finds. His goal is to win more than 200 points.

What is simplification?

The process in mathematics to operate and interpret the function to make the function or expression simple or more understandable is called simplifying and the process is called simplification.

Here,
1 coin = 25 points
For 200 points number of coins is given as = 200 / 25 = 8 coins

Thus, the required number of gold coins he needs is given 8 coins.

Learn more about simplification here:

https://brainly.com/question/12501526

#SPJ2


The regular price of a CD player is $89. It is on sale at a 25% discount. What is the sale price of the CD player?

Answers

Answer:

$66.75

Step-by-step explanation:

You would multiply $89 by .25 to find out what 25% is, then subtract that from $89 to get $66.75

Answer:

$66.75

Step-by-step explanation:

There are 96 crayons in a box. Janice takes 9 crayons. How many are left?​

Answers

Answer:

87

Step-by-step explanation:

Answer:

87 crayons

Step-by-step explanation:

96-9=87

Need help with this

Answers

Answer:

The value of x is 25

Step-by-step explanation:

A secant is a line that intersects a circle in exactly two points. When two secants, intersect at a point outside a circle then the measure of the angle formed between them is one-half the positive difference of the measures of the intercepted arcs

In the given figure

→ In circle O

∵ GB and GD intersect it at points F, B, and E, D

GB and GD are secants of circle O

∵ GB and GD intersect outside the circle O at point G

∵ They intercepted arcs EF and BD

→ By using the rule above

m∠G = [tex]\frac{1}{2}[/tex] (m arc BD - m arc EF)

∵ m arc BD = m arc BC + m arc CD

∵ m arc BC = 35° and m arc CD = 100°

m arc BD = 35 + 100 = 135°

m arc EF = x

m∠G = 55°

→ Substitute them in the rule above

55 = [tex]\frac{1}{2}[/tex] (135 - x)

→ Multiply both sides by 2 to cancel the fraction [tex]\frac{1}{2}[/tex]

∵ 110 = 135 - x

→ Subtract 135 from both sides

∴ -25 = -x

→ Divide both sides by -1

25 = x

The value of x is 25

-5 ≤ -2; Add 7 to both sides

Help pls

Answers

Answer:

2 ≤ 5

Step-by-step explanation:

-5 ≤ -2 add 7 to both sides

-5+7 ≤ -2+7 calculate

2 ≤ 5

Find the value of x​

Answers

Answer: x= 108

Step-by-step explanation: The triangle is an isosceles triangle, so the two sides are parallel which means the other angle equals to 72 as well. Now we take the triangle rule and do 180-72-72= 36 (the top angle= 36). The triangles are all equal so that means the other angle (in the upside down one) also equals 72 so we take 36+72= 108. Since it is also a parallelogram, the angles are equal.


f) Cosec2A + Cot4A = CotA – Cosec4A

Answers

Answer:

True (the sides are equal)

I hope this helps!

Help me ASAP pls with this

Answers

Answer:-15,20

Step-by-step explanation:

-15 and then 20 :) I hope this helps

pls help this is due today!!! if correct I'll make Brainliest!!!!​

Answers

1= 1/8

2= 4/8

3= 2/8

Step-by-step explanation:

The probablity would be 3/4
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Take a few minutes to write a short paragraph describing anexperience you have recently had. Pick a location you went to or an event you attended. Once you have finished, readover what you have written. Now, write a second paragraph. In it, you will repeat the information from the firstparagraph, but you will choose your words more carefully. Ask yourself questions like: What words capture this imageexactly? What is the best word to convey how something looked, or how I felt? Take more time with the secondparagraph.Your response should be at least 150 words in total. Debt is a big problem for Americans. Almost 40% of Americans have some kind of credit card debt, and an average household carriesanywhere from $7,000 to $15,000 in credit card debt at any given time. Some people say that the credit card companies' unethical actionsare to blame. These companies bombard people with offers for available credit, reel them in, and then, due to interest and finance charges,individuals are "on the hook" for years trying to pay off their debts. Other people say that those who are in debt are to blame. It's everyone'sresponsibility to manage her/his own finances wisely and not to charge purchases that can't be paid off. What do you think? A teacher buys 5 pizzas. Each slice is 1/8 of a pizza. How many slices are there in total? 1/40 slice 4 slices 20 slices 40 slices I have been sitting on a chair for the last 3 years, now the chair is growing into me. i feel refreshed A species of plant produces purple or white flowers. The results of crossing a purple and a white flower and two white flowers are shown in the diagram. Which of the following terms best describes the purple flowers? A. recessiveB. Dominant C. hybridD. codominant someone help me pleaseeee Choose the best answer. Quin grit? Esmeralda grita. Esmeralda grit. 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It's no wonder, then, that this ancient shark left so many of them behind. 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