A laptop computer consumes about 20 watts of electricity per hour when operating. At 10 cents per kilowatt-hour, how much does a laptop cost to operate for 5 hours

Can someone me with #s 8, 9, and 11. with just one of the three also works. prove using only trig identities.

Apiling for a high-rise building is pushed by two bulldozers at exactly the same time. one bulldozer exerts a force of 1250 pounds in a westerly direction. the other bulldozer pushes the piling with a force of 2650 pounds in a northerly direction. what is the direction of the resulting force upon the piling, to the nearest degree? a. 65 n of w b. 25 n of w c. 45 n of w d. 35 n of w

Mr. vector door is buying two new cowboy hats all together the hats cost $75.12 the second heart cost twice as much as the first hat what is the price of the more expensive at round to the nearest hundredth