Answer:
t=0.08 seconds or 2.49 seconds
Explanation:
using x= ut + 0.5at^2
x = 1
u=12.6m/s
a= -9.8m/s^2. (since it's moving upward )
1=12.6t - (0.5×9.8× t^2)
1= 12.6t - 4.9 t^2
4.9 t^2-12.6t+1=0
solving for t using quadratic formula
t=0.08 seconds or 2.49 seconds