Stars that are medium-sized are more than ten times the size of our sun. less than half the size of our sun. about the size of our sun. about four times the size of our sun.

Efficiency is the percent of work put into a machine by the user (input work) that becomes work done by the machine (output work)

Aeukaryotic cell must be from a plant if the cell a) a nucleus b) a nuclear envelope c) cytoplasm d) a cell wall

Which of the following can be reduced by the use of renewable energy sources? a. social costs b. economic costs c. environmental costs d. all of the above select the best answer from the choices provided a b c d