Please i need help with all of them but even if you answer one ill be happy

Segment an is an altitude of right δabc with a right angle at a. if ab = 2, squared 5 in and nc = 1 in, find bn, an, ac.

The track team ran a mile and a quarter during their practice how many kilometers did her team runs?

Aclassmate thinks that solving a system by graphing gives an exact answer when the lines appear to cross at a grid point, but only an approximate answer when they don't. explain why this isn't true.