Each cell has a size and shape that is suited to its job.
He proposed the scientific method. He thought it was best to base a theory on observation instead of think of a theory and then try to prove it. So the answer would be A.
Answer:
121km/h
Explanation:
Let speed of boat=xkm/h
Speed of water flow=33 km/h
Speed upstream=(x-33)km/h
Speed downstream=(x+33)km/h
Time=44 hrs
Time =77 hrs
We have to find the speed of boat.

Using the formula
Upstream distance=Downstream distance





Hence, the speed of boat=121km/h