If two resistors with resistances R. and R2 are connected in parallel, as in the gure, then the total resistance R, measured in ohms (Q), is given by i _ L L R R: R2 If R: and R2 are increasing at rates of 0.3 (1/5 and 0.2 (1/5, respectively, how fast is R changing when R. = 80 Q and R2 = 100