The table below shows the size of a firm measured in terms of number of employees and the type of firm are related to. The joint probabilities in the Table 2 were calculated. Number of employees Under 20 20-99 100 or more Total Construction a 0.019 0.002 0.252 Table 2 Industry Manufacturing 0.099 b 0.015 d Retail 0.501 0.088 0.011 0.6 Total 0.831 0.142 1 4/13 a) What is the value for a, b, c, and d? b) Find the probability a firm employs fewer than 20 employees? c) What probability of the firm in the retail industry or have 100 or more? d) Find the probability that a firm in the construction industry employs and 20 to 99 workers. (III) (2 Marks) e) Determine P(Construction I Under 20). (1 Mark) (2 Marks)