What expression is equal to (3d^4)^2

For which pair of functions is (gof)(a)=|a|-2?

If a || b and b | y, then ? a) x || y. b) x | a. c) a | y. d) a || y.

Lin is writing an equation to model the proportional relationship between y, the total cost in dollars of downloading videos from a website, and x, the number of videos downloaded. she knows that the total cost to download 3 videos was $12. her work to find the equation is shown below. joylin’s work step 1 k= 3/12= 0.25 step 2 y= 0.25x where did joylin make her first error?