Answer
(a) $v_x, a_x,$ and $a_y$ are constant during the flight.
(b) $a_x = 0$ throughout the flight.
Work Step by Step
(a) $v_x, a_x,$ and $a_y$ are constant during the flight.
The $x$ and $y$ positions change during the flight, so they are not constant.
Because of gravity, $v_y$ decreases throughout the flight so it is not constant.
$v_x$ is constant throughout the flight as there is no horizontal acceleration.
$a_x$ is constant and equal to zero because there is no horizontal force during the flight (when we ignore air resistance).
$a_y$ is constant (equal to $g$) throughout the flight and it is directed toward the ground.
(b) $a_x = 0$ throughout the flight because there is no horizontal force acting on the object during the flight (assuming we ignore air resistance).