Please help I’m on a test

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

Explain two reasons you think it is important for scientists to search for new ways to treat cancer

Darrel conducted an experiment with the following procedure: fill two cups with ice water. place an uninflated balloon snuggly onto your left index finger. blow a little air into an identical balloon, and place it onto your right index finger. place both fingers into the cups of ice water. darrel noticed that his right finger felt warmer in the ice water than did his left finger. which of the following does the experiment show? a. air is a good radiator of heat. b. air is a good insulator of heat. c. air is a good conductor of heat. d. air is a good convector of heat.