Which statement describes a compound machine? a. it has movement in only one direction. b. it can only be acted on by one force. c. it is made up of more than one simple machine. d. it makes work more difficult.

Which of the following statements about archaea and bacteria is true? a. neither is single-celled. b. they both have nuclear membranes. c. neither reproduces by binary fission. d. they both lack a nuclear membrane.

Why is it important to study each branch of earth science?

Which step is not included in the step approach to calculating the greatest common divisor?