Question

Main aim of using oil in O.C.B. is -
1) Insulation 2)To restrict entry of outside air 3) Enabling operation at tha minimum temperature 4)To quench the sparking in the contacts

Answer 1

Here Is Your Answer, Friend!
_⭐___⭐___⭐___⭐____⭐__

[3] Enabling operation at tha minimum temperature.

Answer 2

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ᏟᎾᏒᏒᎬᏟᏆ ᎾᏢᏆᎥᎾᏁ - - - - - - -

❖ ➙ [b]

It seems to the best option and sounds well from all the other options.

So, l have marked the above option as the best option.

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✭✮ӇƠƤЄ ƖƬ ӇЄԼƤ MƛƳ ƳƠƲ✭✮
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