A train rolls past a stationary observer. To him, the train is moving at a speed
of 25 m/s west, and a woman on the train is moving at a speed of 24.6 m/s
west. How long does it take the woman to move 4 m relative to the train?
A. 7.1 s
B. 9.0 s
C. 8.4 s
D. 10 s

Several mountains together form a mountain . a few of these combined form a mountain system. several systems combined form a mountain , which can stretch thousands of miles in length.

Under the action of a constant force an object accelerates at 7.8 m/s2. what will the acceleration be if (a) the force is halved? (b) the object's mass is halved? (c) the force and the object's mass are both halved? (d) the force is halved and the object's mass is doubled?

Which additional product balances the reaction h2so4 + 2naoh → na2so4 + 2h2o 2oh h2o2 h3o