Absolute value symbols are needed when you simplify some of these expressions. which ones are they?

Multiplying an even number of negative numbers gives an answer that is choose from:

The two cylinders are similar. if the ratio of their surface areas is 9/1.44 find the volume of each cylinder. round your answer to the nearest hundredth. a. small cylinder: 152.00 m3 large cylinder: 950.02 m3 b. small cylinder: 972.14 m3 large cylinder: 12,924.24 m3 c. small cylinder: 851.22 m3 large cylinder: 13,300.25 m3 d. small cylinder: 682.95 m3 large cylinder: 13,539.68 m3

You buy 4 items that cost 2.69 14.45 8.05 13.95 what is the estimated total round to the nearest dollar