Answer to Question 1
The world's fresh water comes from evaporation of salt water. Solar energy is
necessary for evaporating that water from the ocean. When the salt water mixes with fresh
water, some of that solar energy is recovered (some solar energy went into gravitational
potential energy, and that was recovered as the water fell as rain.
Answer to Question 2
The circuit breaker disconnects a circuit if the current exceeds a specified amount.