It was the invention of the that made it possible for scientists to discover and learn about cells.
a. microscope
b. beaker
c. ruler
d. magnifying glass

Which characteristics are typical of a human population in the postindustrial stage?

Which structure in the cardiovascular system connect arteries to veins?

Science which of the following is an example of a cyclic behavior that is seasonal? i think the answer is d, i just need to double check : ). a. running from predators. b. searching for water. c. hunting at night. d. migrating for warmth. ***