For each business analytics question below, identify the questions it is answering. Choose from this list:

a$.$ What happened? What is happening?

b$.$ Why did it happen? What are the causes of past results?

c$.$ Will it happen in the future? What is the probability something will happen? Can we forecast what will happen?

d$.$ What should we do$,$ based on what we expect will happen? How do we optimize our performance based on potential constraints?

e$.$ How can we continuously learn using artificial intelligence? Can we learn from past and current events with adaptive learning?

$\backslash$table$[[$Business Analytics Question$],[$What are the key characteristics of the customers who purchased from us last year?$],[$Why did Delta Airlines' on$-$time departures improve this past month?$],[$What is the expected return on an investment in stocks instead of bonds, based on what we expect$],[$Can we predict how long it will take our vendor to get its products to our distribution center?$],[$Why did our company's import taxes increase last year?$],[$What are the expected sales of bananas next year at the Kroger chain of grocery stores?$],[$Could a computer learn from decisions made by inventory managers in order to auto$-$order supplies$],[$Whose stock is dwindling?$]]$