Which is not true about the variables in the relationship F = ma? A. Acceleration is directly proportional to mass.

B. Force is directly proportional to mass.

C. Force is directly proportional to acceleration.

D. Acceleration will double if force is doubled.

When a book falls from a shelf to the ground without anyone pushing on it, no work is done on the book. true or false

From center station, a train departs every 30 minutes on the fast line and a train departs every 50 minutes on the state line. if two trains depart from center station at 8: 00 a. m., one on each of the two lines, what is the next time that two trains, one on each line, will depart at the same time?

Argon, neon, and xenon are examples of