Which of the following has the largest gravitational potential energy a. a 10kg dog running down the street at 30mph b. a tightrope walker slowly crossing niagara falls c. a 0.02kg bullet moving down the barrel at 800mph d. a semi truck parked in a parking lot

Gravitational potential energy = mgh

Thus it is clear the higher the mass and height, the  more will be the gravitational potential energy

Thus option B is the correct answer

answer: a ball

explanation: because it will bounce

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.