A trash compactor can compress its contents to 0.350 times their original volume and 4 times denser than their original density. Neglecting the mass of air expelled, what factor is the old density of the rubbish

Two resistors r1 and r2 may be connected either in series or parallel across an ideal battery with emf ε. we desire the rate of energy dissipation of the parallel combination to be 8.75 times that of the series combination. if r1 = 105 ω, what are the (a) smaller and (b) larger of the two values of r2 that result in that dissipation rate?