A self-regulated organism takes measures to balance its own survival with the scarce resources that the enviroment offers. In this case, the insect population is self-regulating because it is responding to changes in the food supply, and adapts itself accordingly.
In a way, self-regulation is like supply and demand. As supply of food decreases, but demand stays the same, scarcity ensues. This causes the need to reduce demand until a new equilibrium is reached, where demand and supply are equal.
First use this equation to find the wave speed: vms== =τµ/ 0.4/ 0.001 20 / Then use the equation for solving frequency of a wavelength, and solve for wavelength λ = v/f = 20/100 = .2 m = 20 cm.