In this task, you need to answer the given multiple-choice question on the physics. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.
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Question: Problem: a cistern of capacity 8000 litres measures externally 3.3 m by 2.6 m by 1.2 m and its walls are 5 cm thick . the thickness of the bottom is : 
Options: a ) 90 cm , b ) 2 dm , c ) 1 m , d ) 1.1 cm , e ) none of these

Answer: b


Question: Problem: a man can row upstream at 26 kmph and downstream at 30 kmph , and then find the speed of the man in still water ? 
Options: a ) 29 , b ) 28 , c ) 30 , d ) 32 , e ) 23

Answer: b


Question: Problem: a man can do a job in 15 days . his father takes 20 days and his son finishes it in 15 days . how long will they take to complete the job if they all work together ? 
Options: a ) 6.3 , b ) 6.9 , c ) 5.5 , d ) 6.1 , e ) 6.2

Answer:
c