Q value of a good mediumwave receiver must be approximately 100. Why?

Find the approximate value of sqrt401 .

Find the approximate value of sqrt0.037 .

Time period of a particle in SHM is T=2pisqrt(m/k) . A simple pendulum executes SHM approximately. Why then is the time period of pendulum is independent of mass?

BCl_3 is a good Lewis acid. Why?