A self$-$contained bearing uses an oil bath lubricating system. The effective area of the housing surface is $25000m{m}^2.$ The bearing heat generation rate is calculated to be $25\frac{J}{s}.$ Determine the average film temperature. Assume shaft$-$stirred air at $20C$ with $=1.$

$($a$)135C$

$($b$)150\mathrm{.}7C$

$($c$),44\mathrm{.}2C$

$($d$)32\mathrm{.}5C$