A spring-mass oscillator is used in a mechanical clock to be exhibited during the school's science fair. It consists of two springs, with spring constants k₁ and k₂, where k₁=k₂/4, and bob of mass m, as shown below. Derive an expression for the bob’s oscillation frequency f in terms of the frequencies f₁ and f₂ at which it would oscillate if attached to spring 1 or spring 2 alone.