Composition of Functions Help!

Is the product of two rational numbers irrational or rational? first, make a hypothesis by multiplying two rational numbers. then, use variables such as x=a/b and y=c/d and the closure property of integers to prove your hypothesis.

What is the effect on the graph of the function f(x)=x when f(x) is replaced with -f(x)+4

Jonathan can throw a baseball 10 1/3 yards. his brother joey can throw a baseball 13 1/2 yards. how much father can joey throw the ball?