Ying reaches his lowest altitude immediately after diving.
To find the lowest altitude that Ying reaches, we need to calculate the distance traveled in the vertical direction. Assuming there is no initial vertical velocity, we can use the kinematic equation:
d = 1/2gt^2
where d is the distance, g is the acceleration due to gravity, and t is the time. In this case, t is the time it takes for Ying to reach the lowest altitude after diving. Since we are not given the value of g, we can use the approximate value of 9.8 m/s^2 for the acceleration due to gravity.
Using the equation, we can solve for t:
0 = 1/2(9.8)t^2
Simplifying the equation gives:
t^2 = 0
Since t^2 is equal to 0, we can deduce that t is equal to 0. Therefore, Ying reaches his lowest altitude immediately after diving.