In a circular motion of a particle, the tangential acceleration of the particle is given by $a_{t}=2 t \mathrm{~m} /$ $\mathrm{sec}^{2}$, where $t$ is the time of motion. The radius of the circle described is $R=2 \mathrm{~m}$. 'lhe particle is initially at rest. $\Lambda$ t time $t$, the total acceleration of the particle makes an angle $45^{\circ}$ with radial acceleration. Choose the correct alternatives.
(a) 'lhe value of $t$ is $2^{3 / 3} \mathrm{~s}$.
(b) The value of $t$ is $2^{1 / 3} s$.
(c) The total acceleration of the particle when $t=1$ s is $\sqrt{17} / 2 \mathrm{~m} / \mathrm{s}^{2}$.
(d) The total acceleration of the particle when $t=1$ s is $1 / 4 \mathrm{~m} / \mathrm{s}^{2}$.