How to find the volume of a parallelepiped with 8 vertices?

Name the most appropriate metric unit for each measurement like the mass of cow

If f(x) =3x-2 and g(x) =2x+1 fins (f+ g) (x)

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? $$