Tangential acceleration of a particle moving on a circle of radius $1 \mathrm{m}$ varies with time $t$ as shown in the graph (initial velocity of the particle is zero). Time after which total acceleration of particle makes an angle of $30°$ with radial acceleration is

Given is the $\alpha$$-t$ graph for a car wheel, where brakes produce an angular acceleration $\alpha .$ Which of the following can be the form of $\theta -$$t$ graph?

For the given situation as shown in the graph, the initial angular velocity of the particle is $2\mathrm{\pi } \mathrm{rad} {\mathrm{s}}^{-1}.$ What will be the final angular velocity if the particle follows the given $\alpha -$ $t$ graph?