31. a ball is thrown straight down at a speed of 3.0 m/s and accelerates under the pull of gravity for 2.0 secs. How fast is it moving ?

answer: 802.3 kilo joules of energy represents 191.75 kilo calorie of energy.

explanation:

energy released during combustion of one mole methane = 802.3 kilo joules

if 1 kilo joule = 0.239006   kilo calorie

then ,802.3 kilo joule will be = 802.30.239006 kilo calorie

802.3 kilo joule = 191.75 kilo calorie

hence, the energy in kilo calorie is 191.75 kilo calorie.

it has to be b, about 97 percent.

attach the statements so i can answer : )

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