To answer this question, its better to use only the first half of the parabolic path taken by the gymnast. Hence, it's best to start off by listing all your known values:

u

_{h} = ucos(28) m/s ---> can be derived from a vector diagram

u

_{v} = usin(28) m/s

a

_{h} = 0 m/s^2

a

_{v} = -10 m/s^2

v

_{h} = ucos(28) m/s ---> stays the same

v

_{v} = 0 m/s

x

_{h} = 1.25 m

Note: x

_{h}, v

_{h} and v

_{v} are the values taken at the end of

*half* of the parabolic path.

Now, we can use the constant acceleration formulae to calculate the time taken by the gymnast to get to the maximum turning point of her path. The following calculation makes use of horizontal projectile values:

Now that we've got a value for time, we can substitute this value into another formula. The following calculation makes use of vertical projectile values: