Two sound waves in air have wavelengths differing by $$2\ \text{m}$$ at a certain temperature $$T$$. Their notes have musical interval $$1.4$$. Period of the lower pitch note is $$20\ \text{ms}$$. Then, speed of sound in air at this temperature $$T$$ is

A

$$350\ \text{m/s}$$

B

$$342\ \text{m/s}$$

C

$$333\ \text{m/s}$$

D

$$330\ \text{m/s}$$