Aball is thrown at a 60.0° angle above the horizontal across level ground. it is released from a
height of 2.00 m above the ground with a speed of 16.0 m/s. how long does the ball remain in the
air before striking the ground?

Write out what you have which is:
initial velocity 
final velocity 
Y distance 
degree

You do not have :
a
X distance 
t

from what you have you can plug into your formulas to get time.

Answerthe energy required is 1.60 × 10⁻¹⁸ j, to three significant figures.explanationwe define electric potential as the ratio electric potential energy to the charge,    then the following gives us the potential difference,      the formula  may be on your formula sheet.the change in electric potential energy would be the energy that would needed to move it from point a to point b. solving for that, we get    using q = 8.00  × 10⁻¹⁹ c and  δv = 2.00 v, we get    the energy required is 1.60 × 10⁻¹⁸ j, to three significant figures.