Why does a plant cell have a cell wall and a cell membrene while the animal only a membrane?

When should a bar graph be used? a. when there is no independent variable. b. when the independent variable is continuous and does not show a relationship to the dependent variable. c. when the independent variable is continuous and shows a causal link to the dependent variable. d. when the independent variable is composed of categories and does not show a relationship.

Long-period comets come from the oort cloud particles in earth’s atmosphere material from the asteroid belt the kuiper belt

Drag each tile to the correct box. arrange the layers and faults from oldest to youngest.