i just took the test on edg enuity it was B.The mass of the rocket decreases as fuel is burned, so the acceleration increases.
The correct answer that would best complete the given statement above would be the second option. A screw is an inclined plane wrapped around a cylinder. <span>The efficiency of a screw is low because there is more input than output. In other words, it is because of friction. Hope this answer helps.</span>
The trains take <u>57.4 s</u> to pass each other.
Two trains A and B move towards each other. Let A move along the positive x axis and B along the negative x axis.
therefore,

The relative velocity of the train A with respect to B is given by,

If the train B is assumed to be at rest, the train A would appear to move towards it with a speed of 170 km/h.
The trains are a distance d = 2.71 km apart.
Since speed is the distance traveled per unit time, the time taken by the trains to cross each other is given by,

Substitute 2.71 km for d and 170 km/h for 

Express the time in seconds.

Thus, the trains cross each other in <u>57.4 s</u>.