Find the radius of the circle in which a central angle of $60°$ intercepts an are of length $37.4 \mathrm{cm}$$($use $\pi =\frac{22}{7})$.

Find the angle in radian through which a pendulum swings if its length is $75 \mathrm{cm}$ and the tip describes an arc of length $10 \mathrm{cm}$.

Find the angle in radian through which a pendulum swings if its length is $75 \mathrm{cm}$ and the tip describes an arc of length $15 \mathrm{cm}$.