Multiple !

if you had two identical magnets and put them together so that one of the south poles was in contact with the other's north pole, what would you have?
a. one magnet with a stronger north pole
b. one magnet with a stronger south pole
c. one magnet with a north pole and a south pole
d. no magnet since the two smaller magnets would lose their magnetism when combined to form a larger magnet

Which type of wave can travel without a medium

In a system, when potential energy decreases, then entropy also decreases. true false

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