In which of the following situations would a spring scale be used?

Main uses of spring balances are industrial, especially related to weighing heavy loads such as trucks, storage silos, and material carried on a conveyor belt. They are also common in science education as basic accelerators. They are used when the accuracy afforded by other types of scales can be sacrificed for simplicity, cheapness, and robustness.

A spring balance measures the weight of an object by opposing the force of gravity acting with the force of an extended spring. hope you can get some use from this 

in this image, you can see solar radiation going through ocean water.

no image, but probably absorption