When does the waiting period (iddah) for a woman whose husband died end, knowing that his death was on Tuesday, 3/4/2008, and how is the iddah calculated?

The iddah (waiting period) for a non-pregnant woman whose husband has passed away is four months and ten days. This period is calculated starting from the day of the husband's death. One should note the exact time of the husband's death, then calculate the remaining days of the month in which he passed away, followed by four full lunar months. After that, ten days are added from the subsequent month, so that the iddah concludes at the same time on the last day as the time of the husband's passing.