A concave lens with focal length -15.5 cm creates a virtual image
-13.5 cm from the lens. If the
image is 6.25 cm tall, what is the
object height?
(Mind your minus signs.)
(Unit = cm)

After a big snowfall, you take your favorite rocket-powered sled out to a wide field. the field is 195 m across, and you know that your sled accelerates at a rate of 3.65 m/s2 when the rocket is on. how much time will it take the sled to cross the field starting from rest, assuming the rocket is on the whole time?

How are the crust and the inner core alike? a) they are both solid. b) they both have the same temperature. c) they are both under the same pressure. d) they are both very close to the center of the earth.

What is the equation for electrical work?