Answer:
a)
, b) 
Explanation:
a) The equation for vertical velocity is obtained by deriving the function with respect to time:

The velocities at given instants are, respectivelly:


Answer: be alert for pedestrians near the bus.
Explanation: Due to road accidents many Governments around the world has adopted and put in place certain rules and regulations with regards to road safety, this is so to prevent the or reduce the chances of accidents happening.
Road safety rules are rules and guidelines put in place by Government in order to prevent road accidents and maintain a free flow of traffic. An example of such rules is 'be alert for pedestrians near the bus ' when approaching a local bus that is stopped.
Answer:
mass = 61.16 kg
Explanation:
given data
distance = 50 m
energy = 500 W = 500 × 60sec = 30000 J/min
to find out
mass
solution
we will apply here energy equation
that is
energy = m×g×h .............1
put here all value m mass here and g = 9.81 and h is distance
energy = m×g×h
30000 = m×9.81×50
mass = 61.16 kg