·does a change in the initial speed change the time of flight? If so, how?

Explanation:

When an object is thrown at an angle θ with the horizontal . It covers the parabolic path . We can calculate the  time of flight by the relation

T =

here u is the initial velocity and g is acceleration due to gravity .

and T is time of flight .

Thus if we increase the initial velocity , the time of flight also increases and vice versa .

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.

gas and liquid