A small copper $($density $=8950K\frac{g}{m^3}$ and specific heat $\{$:$=380\frac{J}{K}g.C)$ cube of

dimensions $1cm1cm1cm$ initially at room temperature of $27C$ is exposed to a

hot environment maintained at $200C$ with a heat transfer coefficient of $25\frac{W}{m^2}C$ for

$4$ minutes. Assuming a small Biot number, the temperature of the cube at its center will

be