Using Eq. (10.84), estimate the adiabatic sound speed of the dense core of the giant molecular cloud discussed in Examples 12.2.1 and 12.2.2. Use this speed to find the amount of time required for a sound wave to cross the cloud, ts=2RJ/vs, and compare your answer to the estimate of the free-fall time found in Example 12.2.2. Explain your result.