Nutrient rich soil
usually infertile
found in river deltas
found near the base or mountains
contains low levels of potassium

Found in river deltas

Nutrient rich soil is found in the river deltas.

Option B

Explanation:

The river delta contains soil that is deposited in the river bed by various rivers. These rivers flow through a large land surfaces and thereby bring  in enormous amount of nutrient.

Each biotic environment will have a specific type of nutrient that are produced in abundance due to the type of organisms that dwell there, thereby a river delta will contain the silt that is deposited from the various environments through which the river is flowing.

50% lit on the left side

before, trains worked using the steam engine. thus, it uses heat so it is crucial to apply heat balance. the steam engine absorbs energy during the stage of boiling water. so, this is the endothermic reaction. when the steam is used to work the piston, it has to release this energy through running the train. the excess energy is released as an exhaust to the chimney. this is the exothermic process because it releases energy to the surroundings.