A photographer uses a light meter to measure the intensity of light from a flash bulb. The intensity for the flash bulb, I, measured in lux, is a function of the distance from the light, d,,measured in metres, and can be represented by 10 ,d>0 I(d)=d> a) Determine the following, to two decimal places. i) the average rate of change in the intensity of light for the interval [2,4] ii) the approximate instantaneous rate of change in the intensity of light at exactly 5 m from the flash bulb. 16 b) What does the sign of your answer to part a), subpart ii), indicate about the light intensity?