A box in a certain supply room contains four 30W lightbulbs,five 60W lightbulbs, and six 70W lightbulbs. Suppose that fourlightbulbs are randomly selected. 1) What is the probability thatat least one lightbulb of each type is selected? 2)Find theexpected number of lightbulbs (incorrect ones) that need to beselected before a 60W or 70W lightbulb is selected. Show this bybuilding a probability table.
