Please help! Reporting wrong answers

Use set builder notation to represent the following set: { -3, -2, -1, 0}

Given the functions, f(x) = 2x^2 - 1 and g(x) = 5x, find f(g(x)) and g(f(

The price of a lawn mower is x dollars. the store is having a 75% end of summer clearance sale. which expression can be used to find the clearance price of the mower? a) .25x b) .75x c) x - .25(75) d) x + .25(75)