Now, let us look at needs specifications. Basically what we are following is verification and validation, because needs data specify the requirements cannot be tested by any other method. So, we are to go through an extensive verification and validation sort of it. First you review the needs specifications. As for the errors made, the review can find them out with two units of cost, if you remember one of those earlier graphs. The same thing if we miss probably it will cost ninety times more about 180 units to find out the faults. Second probably those faults we may not really be able to find out those become invisible and elusive. We have to put in great effort to look at them. So a review of the needs specification is a very important way of going through the testing of the specifications or the needs or the requirements.

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