Waves that do not need a medium to transfer energy are called A. Transverse Waves
B. Mechanical Waves
C. Electromagnetic Waves
D. Longitudinal Waves
(help for science Test)​

To create electromagnetic induction, which of the following has to move? a. a wire b. a magnet c. a transformer d. either a or b

How much force was applied to an object if was moved 2 meters and the work done on the object was 8 joules? a. 0.25 n b. 4 n c. 6 n d. 16 n

Air is to be preheated by hot exhaust gases in a cross-flow heat exchanger before it enters the furnace. air enters the heat exchanger at 95 kpa and 20°c at a rate of 0.6 m^3/s. the combustion gases (cp = 1.10 kj/kg°c) enter at 160°c at a rate of 0.95 kg/s and leave at 95°c. determine the rate of heat transfer to the air and its outlet temperature.