chemist wished to find the volume of a large barrel and had no equipment for measuring the amount of water needed to fit it. He added of 400g of pure sodium chloride barrel and filled with chlorine free water. After thorough mixing a 100 ml sample of the solution re

answer;

18.5 seconds

explanation;

velocity is distance covered per unit time; it is given by displacement divided by time.

thus; time = displacement/velocity

total time = total displacement/velocity

total distance = 5000 meters south

total time = 5000/4.5

                  = 1111.11 seconds

but; 1 minute = 60 sec

thus; 1111.11 /60

                = 18.51 seconds

thus; the time taken is 18.5 seconds