How many joules of heat are needed to raise the temperature of 10.0 g of aluminum from 22 degrees celcius to 55 degrees celcius, if the specific heat of aluminum is 0.90 joules?

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?