Answer question 11 part b

Dear student

v = u + at
So, u = v -at
v= 100 km/hr
t = 2 hr.
a = 15 km/hr²
u = 100 - 2 * 15
   =  100 - 30
   = 70 km /hr  
So the initial velocity of the bus was 70 km / hr.

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