Fig. 8.41 represents the velocity-time graph for a lift in a department store
a) Briefly describe the motion represented by OA AB, BC on the
b) Use the graph to calculate the (1) acceleration of the lift and
the total distance travelled by the lift​

It's because 3 if it was 10 it wouldn't look right do it goes up to 4d

Gas will most likely  fill the container 

Distance covered = speed x timethe distance traveled going against the stream = distance traveled with the stream.therefore it is the speed and the time that are the variables.as he travels the same distance both ways, speed x time is the same for each way.going upstream his speed is 4 kph; going downstream his speed is 6 kph.therefore we have two simultaneous equations: time upstream x 4 = time downstream x 6time upstream + time downstream = 60 minutestherefore we have the equation: time upstream = 6/10 hour, time downstream therefore = 4/10 hour.distance traveled at 4km/hr in 6/10 hour = 24/10 = 2.4km.check: distance traveled at 6km/hr in 4/10 hour = 24/10 = 2.4km.