how to solve these question?

22 Marks: 2 In a Poisson distribution with mean 1, the recurrence relation between P(x) and P(x + 1) is given by Choose one answer. O a. AP(x+1)-P(x)=0 O b. P(x+1)-AP(x)=0 O c. (x+1)P(x+1)-AP(x)=0 O d. (x+1)P(x)-xP(x+1)=0 23 Marks: 2 Half of the observations in a data set are greater than the Choose one answer. O a. mode O b. mean O c. standard deviation O d. median 24 Marks: 2 What is the variance for the following set of scores: 2, 2, 2, 2, 2? Choose one answer. O a. 0 O b. 24 O C. 2 O d. 5