Answer:
Explanation:
mass of first marble 
Initial velocity of the first marble
considering right side as positive
Mass of second marble
After collision first marble moves to the left with a velocity of 18 cm/s
i.e. 
considering
be the velocity of second marble after collision
The Coefficient of restitution is 1 for an elastic collision

Putting values

So, the velocity of the second marble is 22.5 m/s to the right after the collision
(b)Initial kinetic energy =
Final kinetic energy=

First, let's list everything we have...
a = 1.83 m/s^2
F = 1870 N (converted from kN to N)
vi = 0 m/s (it says started from rest, therefore velocity starts at 0)
t = 16 s
1). "Force acting on the car" is a bit ambiguous because there are many forces. But I'm going to assume that they are looking for just a basic implementation of force equation:

where:
F = force
m = mass
a = acceleration
2). I recommend memorizing your equations of motion, because once you know them this part is also just as easy:

where:
vf = final velocity
vi = initial velocity
a = acceleration
t = time
Power=work/time
So,
Power =450/50=9watts
The sun's energy flow through the earth's system by it moving through the earth's atmosphere.