A motor cycle starts from rest and accelerates along a straight path at $2{\text{m/s}}^2$. At the starting point of the motor cycle there is a stationary electric siren. How far has the motor cycle gone when the driver hears the frequency of the siren at $94\%$ of its value when the motor cycle was at rest? (speed of sound $=330{\text{m s}}^{-1}$).

1. A
   $49\text{m}$
2. B
   $98\text{m}$
3. C
   $147\text{m}$
4. D
   $196\text{m}$