Question

several scientists are working together to study the change in the number of whales born each year along the northern coast of California. What is the controlled parameter

Answer 1

I believe that in this case the controlled parameter is the type of animal that they are observing. There are a lot of animals in the ocean, therefore to have a scope of their study of observation, they are controlling or limiting their observations on the whale alone. Hence the controlled parameter is the type of animals, whales.