Answer:
d_t = 3.05km
v_a = 4.3km/h
Explanation:
42mins*(2/3) = 28mins
42mins-28mins = 14mins
d = v*t
d_1 = (4km/h)*(1h/60mins)*(28mins)
d_1 = 1.87km
d_2 = (5km/h)*(1h/60mins)*(14mins)
d_2 = 1.17km
d_t = d_1+d_2
d_t = 1.87km+1.17km
d_t = 3.05km
v_a = (v_1+v_2)/2
v_a = [(2*4km/h)+5km/h)]/3
v_a = 4.3km/h
