I need help, for physics

The image shows a pendulum in simple harmonic motion the pendulum starts at a and swing to e

Simple machines can a. increase force only b. decrease force only c. increase or decrease force

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.