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An electric kettle has two heating eleme...

An electric kettle has two heating elements. When one element is connected to an a.c. source the water boils in 10 min. When the other element is used the water boils in 40 min. If both elements are connected in parallel, the time taken by same quantity of water to boil is

A

4 min

B

25 min

C

15 min

D

8 min

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