CALCULATE: Ken is a bicyclist. He is moving from point C to point D up a hill. His starting velocity is 8m/s east and 1 second later, his final velocity is at 7m/s east. What is his average acceleration? HINT: use the acceleration formula. A. 1 m/s^2. B. 7.5 m/s^2east. C. -1m/s^2 east. D. 10 m/s^2east.