Will give brainliest! if right!

a bag contains 5 red marbles, 7 green marbles, and 3 yellow marbles. if a marble
is drawn at random, what is the probability that the marble will be yellow?

a 1/5
b 4/5
c 1/4
d 3/4

Icould really use some with this question.

Ms.ortiz sells tomatoes wholesale. the function p(x)=-80x^2+320x-10, graphed below, indicates how much profit she makes on a load of tomatoes if she makes on a load of tomatoes if she sells them for 4-x dollars per kilogram. what should ms.ortiz charge per kilogram of tomatoes to make on a load of tomatoes?

If x+y+z=0 what is the value of [tex] {x}^{3} + {y}^{3} + {z}^{3} [/tex]