What is the simplest form of 46/8

In a school 2/3 of the students study a language of those who study a language 2/5 study french

Suppose that a households monthly water bill (in dollars) is a linear function of the amount of water the household uses (in hundreds of cubic feet, hcf). when graphed, the function gives a line with slope of 1.65. if the monthly cost for 13 hcf is $46.10 what is the monthly cost for 19 hcf?

Given the two similar triangles, how do i find the missing length? if a=4, b=5, and b'=7.5 find a'