Help with these two questions?

How many kilometers are equal to 5 miles? use 1 mile ≈ 1.61 kilometers. !

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

The multiplicative property of equality states that for real numbers a, b, c, and d, if a = b and c = d, then ac = bd. true false