A metal sphere cools at a rate of $1.5^{\circ} \mathrm{C} / \mathrm{min}$ when its temperature is $80^{\circ} \mathrm{C}$. When the temperature of the sphere is $40^{\circ} \mathrm{C}$, its rate of cooling is $0.3^{\circ} \mathrm{C} / \mathrm{min}$. The temperature of the surrounding $\left(\theta_0\right)$ is

The resultant logic gate from the combination of following gates is

A force acting on a body of mass 5 Kg is $(4 \hat{i}-2 \hat{j}+3 \hat{k}) \mathrm{N}$. If the body is initially at rest then the magnitude of its velocity at the end of 10 second in $\mathrm{m} / \mathrm{s}$ will be

The length of closed and open pipe is same. The ratio of frequency of $\mathrm{n}^{\text {th }}$ overtone for closed pipe to that of open pipe is (Neglect end correction)