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The temperature of a room heated by heat...

The temperature of a room heated by heater is `20^@C` when outside temperature is `-20^@C` and it is `10^@C` when the outside temperature is `-40^@C`. The temperature of the heater is

A

`30^@C`

B

`45^@C`

C

`60^@C`

D

`80^@C`

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SL ARORA-Thermal Properties of Matter-Exercise
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