Ineed i don’t know how to do biology

What are the student's observations and inferences before he starts his investigation?

During convection, less dense fluid rises and denser fluid sinks.

Which statements about a food chain are true? choose all answers that are correct. a.plants are the first living organisms in food chains on land. b. the plants in a food chain are called herbivores. c. all food chains on land begin with energy from the sun. d. carnivores in a food chain eat only plants.