?!?!?!?!?!?!?!!?!?!?

Need this asap if anyone can i would be very grateful. if you could show workings that would really

Mrs. morton has a special reward system for her class. when all her students behave well, she rewards them by putting 3 marbles into a marble jar. when the jar has 100 or more marbles, the students have a party. right now, the the jar has 24 marbles. how could mrs. morton reward the class in order for the students to have a party?

If f(x) = x+8 and g(x) = 4x- 3, find (f+g)(x)