Can someone step by step me answer the ones that aren’t done

At the electronics store you have a coupon for 20% off up to 2 cds you buy for cds with the original cost of $10.99 each the sales tax is 5% what is the total cost of your purchase

Equation for the calculation double 2 and then add 5

Find │7│. a. 1 over 7 b. –7 c. 7 asap i always mark brailiest who me so