Officials begin to release water from a full man-made lake at a rate that would empty the lake in 4 weeks, but a river that can fill the lake in 15 weeks is replenishing the lake at the same time. how many weeks does it take to empty the lake? express your answer as a fraction reduced to lowest terms, if needed.

The discovery of the electron as a subatomic particle was a result of

Adiver named jacques observes a bubble of air rising from the bottom of a lake (where the absolute pressure is 3.50 atm) to the surface (where the pressure is 1.00 atm). the temperature at the bottom is 4.00 ∘c, and the temperature at the surface is 23.0 ∘c.what is the ratio of the volume of the bubble as it reaches the surface (vs) to its volume at the bottom (vb)? if jaques were to hold his breath the air in his lungs would be kept at a constant temperature. would it be safe for jacques to hold his breath while ascending from the bottom of the lake to the surface?

Efficiency is the ratio of to for a system a)power in to power in b)power in to power out c) power out to power out d) power out to power in