Which is a necessary part input for all heat engines? a) steam to act as a working substance b) an energy source, such as fuel or electrticity c) a device to generate electrticity d) luiqid water to act as a working substance

How does the image distance (di) of a convex lens compare with the image distance of a concave lens? a. the image distance of the convex lens is positive, and that of the concave lens is negative. b. both are negative for a virtual image. c. both are positive for a virtual image d. the image distance of the convex lens is negative, and that of the concave lens is positive.

An engineer designs a roller coaster so that a car travels horizontally for 162 ft, then climbs 127 ft at an angle of 31.0° above the horizontal. it then moves 127 ft at an angle of 46.0° below the horizontal. if we take the initial horizontal motion of the car to be along the +x-axis, what is the car's displacement? (give the magnitude of your answer, in ft, to at least four significant figures and give the direction of your answer in degrees counterclockwise from the +x-axis.)

The law of entropy can also be called the law of increasing disorder, but this law seems to contradict the existence of living organisms that are able to organize chemicals into organic molecules. prepare for a class debate on the validity of the following arguments: a. living things are not subject to the laws of thermodynamics. b. the increase in the universe's entropy due to life processes is greater than the decrease in entropy within a living organism.