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.
The Microsoft Excel SUMIFS function adds all numbers in a range of cells, based on a single or multiple criteria. The SUMIFS function is a built-in function in Excel that is categorized as a Math/Trig Function. It can be used as a worksheet function (WS) in Excel. As a worksheet function, the SUMIFS function can be entered as part of a formula in a cell of a worksheet. The syntax for the SUMIFS function in Microsoft Excel is: