Yes. On a circular path, the direction of motion is constantly changing. Change of direction is acceleration, even at constant speed.
Answer: The formula used to solve the problems related to first law of thermodynamics is 
Explanation:
First law of thermodynamics states that the total energy of the system remains conserved. Energy can neither be destroyed, nor be created but it can only be transformed into one form to another.
Its implication is any change in the internal energy will be either due to heat energy or work energy.
Mathematically,

where, Q = heat energy
W = work energy
= Change in internal energy
Sign convention for these energies:
For Q: Heat absorbed will be positive and heat released will be negative.
For W: Work done by the system is negative and work done on the system is positive.
For
: When negative, internal energy is decreasing and when positive, internal energy is increasing.
Hence, the formula used to solve the problems related to first law of thermodynamics is 
Answer: Due that we don't know the initial speed after hitting the ball, we are going to accept that the ball goes up for half of the time and then falls during other half part, that is 3.0 seconds each. Then we know that ball's movement is ruled by the acceleration of gravity formula, as follows: H = Vi * T + 1/2 * g * T^2 V = Vi + g * T where: H is height, Vi initial speed, g gravity acceleration and T time When we only consider the second half of the trajectory, we have that initial speed at the top of that movement is zero, because ball goes up till top, where stops and starts to go down, so : H = 0 * 3 + 1/2 * 32 * 3^2 = 144 ft. So the height of the pop-up is 144 feet.
Yes it is, it was made in France as a gift to the U.S.A.