Which of these equations, if any, does not represent a linear function? (picture included please help!!?

Its worth 10000000 points need asap if you answer correctly ill mark brainliest

Use composition to determine if (x) or h(x) is the inverse of f(x) for the limited domain x2-1.

Julie goes to the sports store and spends $40.50 before tax. she buys a pair of shorts for $21.75 and 3 pairs of socks that each cost the same amount. how much does each pair of socks cost? $$