Event study of a short report

Use the Adani Enterprises and Nifty 50 returns in 6A.13.4. (a) Compute the market-adjusted abnormal returns for 25 January to 2 February 2023, CAR(0, +1) and CAR(0, +5) (trading days). (b) Compute the buy-and-hold return of AEL from the 24 January close to the 2 February close, and the buy-and-hold abnormal return against the Nifty. Why does it differ from CAR(0, +5)? (c) With an estimation-window standard deviation of 1.77% for daily abnormal returns, compute the $t$-statistic for 27 January. (d) Identify two confounding events inside the window and explain how they limit what the study can conclude.