Lightning bolts occur when negative charges in clouds:

A. Flow positively to the ground
B. Flows negatively to the ground
C. Flows to the negatively charged clouds
D. cause thunder to sound

Which simple machine is not part of this compound machine? a. lever b. pulley c. inclined plane d. wheel and axle

30 points - when can a theory be modified if a new type of technology allows for new observations that raise new questions? a. immediately, while the questions about the theory are being asked b. after new hypotheses related to the theory are tested in experiments c. only after the new observations disprove all parts of the theory d. while scientists begin to think about how the theory could improve

When an orange rolls off a table, its potential energy is converted into?