please answer this

2. Consider Card's 1990 work "The Impact of the Mariel Boatlift on the Miami Labor Market." The table below represents the average log wages for Miami and a group of comparison cities. Miami: year 1979 1980 1981 1982 1983 1984 1985 Iwage 1.52 1.54 1.54 1.53 1.48 1.59 1.54 Comp: year 1979 1980 1981 1982 1983 1984 1985 Iwage 1.65 1.63 1.61 1.61 1.58 1.6 1.58 a. If the event occurred in 1980, then define the pre-event period and the post-event period. [5] Hint: include the year of the event in the pre-period since the event occurred later in 1980. b. Determine the DID estimate. Interpret the DID estimate. [20]