While skiing, sam flies down a hill and hits a jump. he has a mass of 75kg and he leaves the jump at 18 m/s what is his momentum as he leaves the jump?

First off, you need to review the formula for momentum:

                     Momentum  =  (mass) times (speed)

                                           =  (75 kg)  x  (18 m/s)

                                           =         1,350 kg-m/s  .   

There it is.  That's all there is to it.

Notice that you would have been sunk without knowing
the equation for momentum.  It's pretty important.  You
should memorize it.  You'll need it again.

Africans having pride in their own culture despite being ruled by people of different cultures gave them a sense of self worth.

Explanation:

The people of Africa were ruled by people of different cultures and by the people from different countries. They had a history of colonial rule where they were a colony of many countries.

But despite being ruled by people of different cultures, the people of Africa had pride in their own culture. This gave these people a sense of self worth. The Africans had pride in their own culture, in their own language and their own nation.