Blood Type Compatibility. Your ABO blood type is based on the presence or absence of the A and B antigens on your red blood cells. The A blood type has only the A antigen and the B blood type has only the B antigen. The AB blood type has both A and B antigens, and the O blood type has neither A nor B antigen.
Green Triangle. The green triangle appears in the upper left hand corner of a cell when there is an error in a formula. Sometimes Excel will report an error when you use text in a box and the program believes it is part of a formula. When you click on the green triangle there will be a yellow box that looks like a road sign with an exclamation point in it. This button is the Trace Error option that will help you correct your formula.
Text to the Left, Numbers to the Right. A quick way to tell if you have either text or number data is to check the alignment of the data in a cell. By default, text data is aligned to the left in Excel and Google Spreadsheets and number data is aligned to the right in a cell. Cell references are a combination of the column letter and row number of a cell-such as A1, B23, and W987 - and are used to identify the location of data in a worksheet. 2  A named range or defined name is similar to a cell reference in that it is used to identify a cell or range of cells in a worksheet.