I'm having trouble with b i and ii. I don't know what the r value is. Also some difficulties in answering. Could someone please help me out with this. Thank you

Question 1 [6 Marks] Suppose 2% of steel rods made by a machine are defective, the defectives occurring at random during production. a) If the rods are packaged 120 per box, what is the mean and variance of the number of defectives per box? b) Calculate the probability that the number of defectives in a box is >1 (i) using the exact binomial distribution, and (ii) using the Poisson distribution with the same mean. c) Is the Poisson distribution a valid approximation to the Binomial here? Justify your