How do you calculate total prices after mark ups/ mark downs? PLEASE HELPP IT'S DUE TODAY :(

Could someone with number 1 and 2

Write the summation to estimate the area under the curve y = 1 + x2 from x = -1 to x = 2 using 3 rectangles and right endpoints

Acomputer store buys a computer system at a cost of $370.80. the selling price was first at $ 618, but then the store advertised a 20 % markdown on the system. answer parts a and b. a. find the current sale price.