A side of cube a is made from 6 identical sheet. If coefficient of linear expansion is $\alpha$ and temperature is now made T + $\Delta$T from temperature T then find change in volume

(1) $\Delta V=3a^3\alpha\Delta T$

(2) $\Delta V={4\over3}\pi a^3\alpha\Delta T$

(3) $\Delta V=4a^3\alpha\Delta T$

(4) $\Delta V=6a^3\alpha\Delta T$

(1) $\Delta V=3a^3\alpha\Delta T$

(2) $\Delta V={4\over3}\pi a^3\alpha\Delta T$

(3) $\Delta V=4a^3\alpha\Delta T$

(4) $\Delta V=6a^3\alpha\Delta T$