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An electric heating coil is connected in...

An electric heating coil is connected in series with resistance of `xOmega` across the 240V mains, the coil being immersed in 1 kilogram of water at `20^@C.` The temperature of the water rises to boiling point in 10 minutes. If the resistance x is short circuited, the time required to produce the same quantity of heat in 6 mins. Sb, the value of x is,

A

`17.9Omega`

B

`5.9Omega`

C

`12.9Omega`

D

`7.9Omega`

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