D=at²
441m=(5*9.81m/s²)(t²)
t²=441/(5*9.81)
t≈√8.99
t≈3 sec
By what i know i think that the answer would be A a homogeneous mixture.
I think the answer is photosynthis, when plants turn light into food and energy.
4A. PE = MxGxH. (You can consider g as 9.8 / 10m/s as well)
509 J = 12x10xH
509 J = 120xH
H = 509/120
H = 4.24 m
Hope u got the answer....pls rate the answer if it is helpful for u....and I'm sorry I could not understand B part so I didn't do it.
Thank you