The expression 4a+2b gives the cost (in dollars) for a sandwiches and b bags of chips at a sandwich shop. a. The cost for 1 sandwich is $ and the cost for 1 bag of chips is $ . b. The total cost for 3 sandwiches and 3 bags of chips is $ . Question 2 c. Is $30 enough to buy 5 sandwiches and 6 bags of chips?

The discrete random variables x and y take integer values with joint probability distribution given by f (x, y) = a(y−x+1) 0 ≤ x ≤ y ≤ 2 or =0 otherwise, where a is a constant. 1 tabulate the distribution and show that a = 0.1.2 find the marginal distributions of x and y. 3 calculate cov(x, y).4 state, giving a reason, whether x and y are independent. 5 calculate e(y|x = 1).