in the four terrestrial planets, the densest, heaviest materials are at the center and not evenly distributed throughout the planet. scientists interpret this observation to mean that:

Technological solutions have good bad effects. what is one bad effect of spraying a chemical pesticide on crops

Summarize the work of famous environmental scientists of the past.

Spider crabs live in the shallow regions of the ocean floor. algae tend to grow on the surface of spider crabs. the algae provide the crabs protection from predators by camouflaging them. the spider crabs give the algae shelter. what does this description suggest? 1. the algae are parasites of the spider crabs. 2. the algae and the spider crabs have a mutualistic relationship. 3. the spider crabs are commensals, and the algae are parasites. 4. the spider crabs benefit from the algae living on them. 5. the spider crabs are parasites of the algae.