The last one.
One grey sphere, Four white spheres, and One red spheres
Answer:
Potential energy = 14.7 Joules.
Explanation:
Given the following data;
Mass, m = 1kg
Height, h = 1.5m
We know that acceleration due to gravity is equal to 9.8m/s²
Potential energy can be defined as an energy possessed by an object or body due to its position.
Mathematically, potential energy is given by the formula;

Where, P.E represents potential energy measured in Joules.
m represents the mass of an object.
g represents acceleration due to gravity measured in meters per seconds square.
h represents the height measured in meters.

Substituting into the equation, we have;

P.E = 14.7 Joules.
Wouldn't mass stay the same and acceleration increase or am I mistaken?
Answer:
The track's angular velocity is W2 = 4.15 in rpm
Explanation:
Momentum angular can be find
I = m*r^2
P = I*W
So to use the conservation
P1 + P2 = 0
I1*W1 + I2*W2 = 0
Solve to w2 to find the angular velocity
0.240kg*0.30m^2*0.79m/s=-1kg*0.30m^2*W2
W2 = 0.435 rad/s
W2 = 4.15 rpm
If F =m*a
and the question says how much force the s needed to accelerate a 68kg skier to a rate of 1.2ms^-2
Then F = 68*1.2