This is a trigonometry question, so you have to use sin cos tan

Twenty-five percent of the customers entering a grocery store between 5 p. m. and 7 p. m. use an express checkout. consider five randomly selected customers, and let x denote the number among the five who use the express checkout.

What is the y-intercept of the line given by the equation

1- 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. 2- 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. 3- 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 part b?