Consider a function that describes how a particular car’s gas mileage depends on its speed. What would be an appropriate domain for this function? 0 to 100 miles per hour
0 to 50 miles per gallon
times from 0 to 10 minutes
times from –10 to 10 minutes

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?

Angles r and s are complementary. the measure of angle r is 31 degrees. which equation can be used to find angle s?

The? half-life of a radioactive substance is 20 years. if you start with some amount of this? substance, what fraction will remain in 120 ? years