The answer to that question is c. tamod
Uh so I'm no master at this subject, but all stuffs accelerate at 9.8 m/s squared. So you multiply the 9.8 and the 0.20 it's given for reasons unknown other than that's what I see in my notes... and that gives you 1.96 m/s squared.
As for B, I have no idea. I think you may multiply the 1.96 by 4. Tell me your thoughts and maybe we can work it out together
Answer:
40000÷40=1000 joules is required to work in 40 seconds
First we need to convert the angular speed from rpm to rad/s. Keeping in mind that


the angular speed is

And so now we can calculate the tangential speed of the child, which is the angular speed times the distance of the child from the center of the motion:
Answer:
0.01606 Newtons
Explanation:
r = Distance between the asteroid and Sally = 17000000 m
m₁ = Mass of the asteroid = 8.7× 10²⁰ kg
m₂ = Mass of Sally = 80 kg
G = Gravitational constant = 6.67 × 10⁻¹¹ m³/kgs²
From Newton's Universal law of gravity

The force Sally experiences is 0.01606 Newtons