Much of the public and private industry in Hawaii depends on tourism. The following time series plot

Question:

Much of the public and private industry in Hawaii depends on tourism. The following time series plot shows the number of domestic visitors to Hawaii by air from the rest of the United States per month from January 2002 through December 2006 before the financial crisis of 2008.

Here is a regression model fit to these data with dummy variables for months and a Time variable that starts at 0 and counts months:

a) Interpret the P-value for the trend coefficient.
b) You are planning to visit Hawaii and hope to avoid the crowds. A friend says that September and November have the fewest average visitors. Why might that not be correct?
c) Do you find evidence of a seasonal effect? Explain.
d) How many tourists would you predict for Hawaii in April 2007 (month 63 of this series)?