(1) The athlete ran forward for 3 seconds, and then he ran backward for 3 more seconds.
(2) The athlete ran forward for 3 seconds, and then he stood still for 3 more seconds.
(3) The athlete ran forward for 3 seconds, and then he ran forward for 3 more seconds but with a lower speed.
(4) The athlete ran forward for 3 seconds, and then he moved forward for 3 more seconds with a greater speed.

In the distance-time graph of a cyclist, what is happening between B-C and C-D?

(1) B-C: cyclist is coming back to where he started, C-D: cyclist is stationary.
(2) B-C: cyclist is stationary, C-D: cyclist is accelerating.
(3) cyclist is stationary, C-D- speed is increasing
(4) B-C: cyclist is stationary, C-D: cyclist is coming back to where he started.

(1)  6 ms^–1
(2)  12 ms^–1
(3)  24 ms^–1
(4)  Zero