(3.25x10^3)(7.8x10^6) written in scientific notation

What is the name used to describe a graph where for some value of x, there exists 2 or more different values of y?

Aproduction manager test 10 toothbrushes and finds that their mean lifetime is 450 hours. she then design sales package of this type of toothbrush. it states that the customers can expect the toothbrush to last approximately 460 hours. this is an example of what phase of inferential statistics

Is it greater than or less than7*3_9*2