A particle is displaced from point $\mathrm{P}(3 \mathrm{~m}, 4 \mathrm{~m}, 5 \mathrm{~m})$ to a point $\mathrm{Q}(2 \mathrm{~m}, 3 \mathrm{~m}, 4 \mathrm{~m})$ under a constant force $\overrightarrow{\mathrm{F}}=(3 \hat{\mathrm{i}}+4 \hat{\mathrm{j}}+5 \hat{\mathrm{k}}) \mathrm{N}$. The work done by the force in this process is

A body of mass 1 kg begins to move under the action of a time dependent force $\overrightarrow{\mathrm{F}}=\left(\hat{\mathrm{t}}+2 t^2 \hat{\mathrm{j}}\right) \mathrm{N}$, where $\hat{i}$ and $\hat{j}$ are unit vectors along $x$ and $y$ axis. The power developed by above force at time $\mathrm{t}=3$ second will be

A stone is projected with kinetic energy E, making an angle $\theta$ with the horizontal. When it reaches a highest point, its kinetic energy is