Answer
3.4 s
Step-by-step explanation
The question can be solve by using the 2nd Newton's law of motion.
s = ut + 1/2at²
Before she is pushed, the initial velocity is zero.
u = 0
Now the equation becomes
s = 0 + 1/2at²
s = 1/2at²
25 = 1/2 × 4.3 × t²
50 = 4.3t²
t² = 50/4.3
= 11.628
t = √11.628
= 3.4 s