It is incorrect to say heavy objects sink in water because based on the density of the water it can actually cause the "heavy object" to float, out weighing it.
Answer:3.49 m/s
Explanation:
Given
Speed of marble at Bottom 
Diameter of loop 
As Energy is conserved therefore Energy at top is equal to energy at bottom

,where
is the velocity at bottom







the answer is heat engine
They made me do it I don’t even know what to say I’m so sorry
There's no way to tell. Without seeing a diagram of the circuit,
I'll need to know much more about it than you've told me.
I don't know anything about the components or power supply
that are in the circuit, and I don't know where point ' f ' is in it.
Right now, even with the copious volume of all the available
information, no answer to your question is possible.