80 foot-pounds of work is needed to move the sofa in tyler's apartment. which of the following statements is true? a.) if tyler moves the sofa himself, he will do more work than if he gets a friend to . b.) if tyler and his roommate move the sofa together, they will do half the amount of work. c.) if the sofa does not move, no work is done. d.)all of the above.

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

Ne way in which elements differ from each other is the structure of the electron cloud in each element's atoms. in an electron cloud, an electron that is farther away from the nucleus has

What do we mean by the event horizon of a black hole?