What is the function ?

The letter tiles shown below are in a bag. whiteout looking i am going to draw one tile. what are my chances of drawing g?

There are 20 children in the cast of a class play and 8 of the children are boys of the boys 4 have a speaking part in the play and of the girls 8 do not have a speaking part in the play if a child from the cast of the place chosen at random what is the probability that the child has a speaking part

A(t)=728(1+0.04)^t how much money did aditya originally invest