A-V Valves Open; Semilunar Valves Closed. This is the first phase of the cardiac cycle. It is initiated by the P wave of the electrocardiogram (ECG), which represents electrical depolarization of the atria. Atrial depolarization initiates contraction of the atrial musculature.
Community Q&A. You can calculate age on Excel for a many applications by combining an undocumented function and the date format for cells. Microsoft Excel internally stores dates as serial numbers, which is the number of days a date is from Jan. 1, 1900.
DAYS function. Applies To: Excel for Android phones Excel Mobile Excel 2016 Excel 2013 Excel 2016 for Mac Excel for Mac 2011 Excel Online Excel for iPad Excel for iPhone Excel for Android tablets More... Less. This article describes the formula syntax and usage of the DAYS function in Microsoft Excel.