Answer : The wavelength is 
Solution : Given,
frequency = 29.2 Hz
Formula used :

where,
= frequency
= wavelength
c = speed of light = 
Now put all the given values in this formula, we get the wavelength.

Therefore, the wavelength is 
Answer:
By minimizing the height of the body's center of gravity relative to its center of buoyancy
Explanation:
In hydrostatics, the equilibrium state of a floating body relates to either a maximum or minimum of the potential energy.An equilibrium is stable when the potential energy is minimum.Minimizing the height of the floating body's center of gravity relative to its center of buoyancy attains a stable equilibrium configuration.

The reaction creates dihydrogen, hence if it's uncontrolled it could lead to potentially dangerous amounts of gas being released at once.