a string with fixed ends is made to go into standing wave patterns. at a given tension, the lowest frequency for which a certain pattern exists is 150 Hz. which of the following frequencies would also cause a standing wave pattern in this case?

Which of the following situations is impossible? a) an object has velocity directed east and acceleration directed east. b) an object has zero velocity but non-zero acceleration. c) an object has constant non-zero velocity and changing acceleration. d) an object has velocity directed east and acceleration directed west. e) an object has constant non-zero acceleration and changing velocity.