What do you think countries should do about population growth? if you were in control of a developing country, how would you slow
population growth?

Many things besides restrictions could slow population growth. We could make birth control a lot more accessible than it is today. Educate people on being responsible parents so that they don't think that you can just leave the child alone when you have it but have to spend decades on the child's growth. Provide more for those communities in the form of living conditions and education since studies show that with the rise of education and better living conditions reproduction slows down.

ek = (m·v2) / 2

v - velocity of system after the collision

m = m1 + m2

ek = (m1 + m2) ·v2/2

ek = (200 + 250) ·2,32/2 = 450·5,29/2 = 1190,25 j