How do i write a 400 word essay on coin density? *cries* ugg im dyin over here :(

Which of the following are properties of mechanical waves? check all that apply ⭕️ particles of the medium move back and fourth, but do not move with the wave. ⭕️ the particles of the medium always move parallel to the wave motion. ⭕️ wave motion begins with a disturbance in the medium. ⭕️ waves transport energy from a source outward, away from the source.

An ideal otto cycle has a compression ratio of 10.5, takes in air at 90 kpa and 40°c, and is repeated 2500 times per minute. using constant specific heats at room temperature, determine the thermal efficiency of this cycle and the rate of heat input if the cycle is to produce 90 kw of power.

Astep up transformer has 250 turns on its primary and 500 turns on it secondary. when the primary is connected to a 200 v and the secondary is connected to a floodlight that draws 5a, what is the power output? show all of your work.