Again, consider the high-frequency data of Boeing stock from December 1 to December 5, 2008. Construct an intraday 5-minute return series. Note that the price of the stock in a 5-minute interval (e.g., 9:30 to 9:35 AM) is the last transaction price within the time interval. For simplicity, ignore overnight returns. Are there serial correlations in the 5-minute return series? Use 10 lags of the ACF and \(5 \%\) significance level to perform of test.