What is the sum of 3/5 + 7/10

Two lines parallel to the same plane are parallel to eachother

Ineed with number 6 , explain how to get 1978

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