Answer :
a) -180m
b) 510-180=+330m
+330/45=7.333m/s
c) total distance = 840m
average speed = 840/105
= 8m/s
b) 510-180=+330m
+330/45=7.333m/s
c) total distance = 840m
average speed = 840/105
= 8m/s