In an experimental investigation, the variable that the researcher changes or manipulates in order to see its effects is called

Test group is a group that is modified or changed by the researcher and is then compared to the experimental group while carrying out an experiment.

Explanation:

While observing the data of the test group, it has to be compared with the control group to see if there is any effect of the treatment on the test or not. The control can be positive or negative or both to which the test group is compared.

hello there the answer is d

ecological efficiency: % of usable energy transferred as

biomass from one trophic level to the next typical is 10% efficient (90% of

energy is lost),is diagramed as the pyramid of energy flow. then osprey eagle

are tertiary consumer and the shrimp are primary consumer, so to balance

mass of shrimp (1/0.1) / 0.1 = 100 kg