A block slides down a frictionless plane that makes an angle of 30 with the horizontal. The acceleration of the block is: A. 980cm/s2 B. 566cm/s2 C. 849cm/s2 D. zero E. 490cm/s2 ans: E A 25N crate slides down a frictionless incline that is 25 above the horizontal. The magnitude of the normal force of the incline on the crate is: A. 11N B. 23N C. 25N D. 100N E. 220N