Why do we use the 2nd order integrated rate equation for ethyl acetate [EA] even though we are told that the reaction is 1st order with respect to ethyl acetate

This flow chart shows the amount of energy that is emitted by each type of light. ultraviolet > blue light > yellow light > red light (maximum energy) (minimum energy) in an experiment, shining which type of light on a strip of metal would be least likely to produce the photoelectric effect? ultraviolet light dim blue light bright red light bright yellow light