A pispn is charging across the plain one morning. His path takes him to location (m, y} at time t, where it: and y are functions of ti and north is in the direction of increasing 1;. The temperature is always colder farther north. As time passes, the sun rises in the sky, sending out more heat, and a cold front lolovvs in from the east. At time t the air temperature H near the Disco is given by H : m, y, t}. The chain rule expresses the derivative dfdt as a sum of three terms: as fm :3fo Elf E 3:33: 5'th as Identify the term that gives the contribution t0 the change in temperature experienced DI)" the pison that is due to: '3' 1 The comin cold front It. 3f 31? v _ . ' 9 as at '2 v 2. The loison's change in latitude 53' B. Eh: v 3. The risin sun '3. 5yE