3. you are walking in paris alongside the eiffel tower and suddenly a croissant smacks you on the head and knocks you to the ground. from your handy dandy tourist guidebook you find that the height of the eiffel tower is 300.5 m. if you neglect air resistance, calculate how many seconds the croissant dropped before it tagged you on the head.

As absurd as the concept is, we must assume that a croissant
can fall 300.5 meters through the moisture-laden, perfumed and
polluted Parisian air with no air resistance whatsoever.

Acceleration due to gravity on Earth:  9.8 m/s²

Distance in clean,
unimpeded free-fall         = (1/2) (acceleration) x (time²) 

                                            300.5 m  =  (1/2)  (9.8 m/s²) (T²)
Divide each side
by (4.9 m/s²):                  (300.5 m) / (4.9 m/s²)  =  T²

Take the square root
of each side:                     T = √(300.5/4.9) (s²)

                                                               =  7.831 seconds .