What percent of values are within the interval (155, 205)?

Plz i want answer and i would appreciate it is is a b c or d

1- what do you think the product of a nonzero rational number and an irrational number is? is it rational or irrational? make use of variables, the closure property of integers, and possibly a proof by contradiction to prove your hypothesis.2- why do we have to specify that the rational number must be nonzero when we determine what the product of a nonzero rational number and an irrational number is? if the rational number were 0, would it give us the same result we found in the first question?

Ithink i know it but i want to be sure so can you me out ?