The energy of bird flight as a function of body weight is given by, E = 429 w−0.35, where w is the weight of the bird (in g) and E is the brain weight (in cal/g/hr). Suppose that the weight of a bird weighing 10 g is increasing at a rate of 0.001 g/hr. Find the rate at which the energy expenditure is changing with respect to time in cal/g/hr/hr to four decimal places.