What happens when an atom is exposed to an energy source such as electricity?

the electrons may jump to a higher energy level.
the electrons move closer to the nucleus.
the electrons may move to a lower energy level.
the electrons emit a continuous spectrum.

What is the length x of the side of the triangle below? (hint: use the cosine function)

The mini-refrigerator fire was most likely caused by what type of wiring?

If a rock is thrown upward on the planet mars with a velocity of 12 m/s, its height (in meters) after t seconds is given by h = 12t − 1.86t2. (a) find the velocity of the rock after two seconds. m/s (b) find the velocity of the rock when t = a. 12−3.72a m/s (c) when will the rock hit the surface? (round your answer to one decimal place.) t = s (d) with what velocity will the rock hit the surface? m/s