<span>When order does not matter you use what is called n choose k formula
n!/(k!(n-k)!) where n is the number of things to choose from and k is the number of choices made, in this case:
20!/(4!(20-4)!)=4845</span>
This can be solved using trigonometric functions. The distance x serves as one leg of a triangle, and makes an angle q with the hypotenuse. The distance from the tip of the rocket to the ground make up the other leg of the triangle. So solving this:
tan q = y / x
Where: y = distance from the tip of the rocket to the ground
Therefore, y = x tan q
Among the choices, the correct answer is C.
37.50 rounded to the nearest tenth is 37.5
It should be 16, but because there is only 2 examples, I'm not totally sure. But, I hope this helps you! :)