You will need to use the information in the table you are given. Subtract: (final velocity - initial velocity) and divide by (final time - initial time).
Leg-A:
Speed = 15km/10min = 1.5 km/min
Leg-B:
Speed = 20km/15min = (1 and 1/3) km/min
Leg-C
Speed = 24km/12min = 2 km/min
Leg-D:
Speed = 36km/9min = 4 km/min
Leg-E:
Speed = 14km/14min = 1 km/min