statistics proability

Question 4 (a) An electronic components manufacturer packages the production units in standard lots, each of them are uniform in size. Past records reveal that the mean number of defective units per lot is 3.5 units. A quality control personnel is about to inspect a lot submitted by the production department, find the probability that the lot will contain: (i) No defective unit. (ii) More than 1 defective units.    ( I WANT HELP HERE ) WITH FULL WORKING AND FORMUALES! DISPLAYED