Answer:
Manipulated or the independent variable is that variable that a scientist change deliberately while the responding or the dependent variable is that variable which changes in response to the changes occur in manipulated variable.
In this experiment, a scientist wants to study the effects of radiation of sun in heating land and water on Earth. Hence, land i.e. soil and water must be the manipulated variable as they are changed deliberately by the scientist.
On the other hand, temperature readings depends upon the phase of matter i.e. soil and water. Hence, the temperature readings are the responding variables.
Time intervals and lamp can be considered as constant variables.
