ANSWER:
7 s
Explanation:
Given:
u = 0m/s
t = 5 sec
g = 9.8 m/s^2
The first thing is to calculate the height of the building, using the following formula:

Now, we apply the same formula, but we substitute the double value of the distance and solve for t, just like this:
![\begin{gathered} 2\cdot122.5=(1)/(2)\cdot9.8\cdot\: t^2 \\ 9.8\cdot t^2=245\cdot2 \\ t^2=(490)/(9.8) \\ t=\sqrt[]{50} \\ t=7.07\text{ sec} \\ t\approx7\text{ sec} \end{gathered}](https://img.qammunity.org/2023/formulas/physics/college/4brjxh7x34kys6ixhpg4opyose30d7cmuo.png)
The time it takes for the object to fall is 7 seconds.