Please solve for all questions

Which statement about perfect cubes is true

You are at a restaurant and owe $38 for your meal. you want to leave a 20% tip. how much will your tip be?

Tabby sells clothing at a retail store, and she earns a commission of 6.25% on all items she sells. last week she sold a pair of jeans for $32.50, a skirt for $18.95, and 2 blouses for $14.95 each. what was tabby's total commission? a $4.15 b $5.08 c $81.35 d $348.60