can someone help

a) Mark and Lisa are two real estate agents. Let X and Y be the respective numbers of houses sold by them in a month. Based on past sales, the following joint probabilities for X and Y are estimated. (i) Calculate the covariance between the houses sold by Mark and Lisa and interpret your finding. [5 marks] (ii) Determine whether the houses sold by Mark and Lisa are statistically independent. [3 marks] (iii) Find the expected value of total houses sold in a month by Mark and Lisa together. [3 marks]