1. A girl drops a ball off the roof of her house. It takes the ball 2 seconds to hit the ground. How tall is the house?

If the acceleration constant..

you can use the formula s = ut + 1/2at²

Known that :

s = ?

u = 0

t = 2s

a = 10ms-²

Then you can apply the formula

s = ut + 1/2at²

s = 0 + 1/2(10)(2)²

s = 5 × 4

s = 20m

Answer : 20m

Explanation :

The gravity can be 9,8 or 10. Also im not sure how people teach you but in my school, if the ball goes down the gravity is positive and not negative thats why i put 10ms-² and not -10ms-²

s = displacement/distance

u = initial speed

a = acceleration

t = time

sorry if im wrong

the plateau is likely to turn into a desert do to corrosion.

i think it’s a. this is because if they measured the mass of something with a mass of 150g, then their final answer would have to be approximately 150g. though all of their answers are almost 150, rosa and tran have the closest answers (or the exact answer) to the accurate one.