What is true of paramecia?

How many trophic levels are there in the following food chain? phytoplankton - shrimp - perch - pike - osprey

Linda and julia are trying to determine whether their ideas are scientific or pseudoscientific. linda's idea is free of bias. julia's idea gives the same result when tested repeatedly. which statement is correct about linda and julia's idea?

Resperation is a way to release carbon back into the atmosphere