Answer:
a) s1 is 4 km/h because it is given. t1 is 30 min. s2 is 8 km/h. d is 4 km because given
b) d2 is 2 km because he travels 30 min at 4 km/h which is 2 km
c) d2 is 2 km because he travels 30 min at 4 km/h which is 2 km and 4 km-2 km is 2 km
d) 2 km at 8 km/hour is 1/4 hour which is 15 minutes so t2 is 15 min.
e) 3:45+15 min is 4:00
