The combined electrical resistance R of two resistors R1 and R2, connected in parallel, is given by the equation below, where R, R1, and R2 are measured in ohms. R1 and R2 are increasing at rates of 0.6 and 1.6 ohms per second, respectively. 1_;+; R _ R1 R2 At what rate is R changing when R1 = 45 ohms and R2 = 90 ohms? (Round your answer to three decimal places.) ohm/sec