Answer :
Heya!
For this problem, use the formula:
s = Vo * t + (at^2) / 2
Since the initial velocity is zero, the formula simplifies like this:
s = (at^2) / 2
Clear a:
2s = at^2
(2s) / t^2 = a
a = (2s) / t^2
Data:
s = Distance = 518 m
t = Time = 7,48 s
a = Aceleration = ¿?
Replace according formula:
a = (2*518 m) / (7,48 s)^2
Resolving:
a = 1036 m / 55,95 s^2
a = 23,34 m/s^2
The aceleration must be 23,34 meters per second squared