Negative testing is testing outside the relm of NORMAL 
testing. If a requirement for a vaild age value input is 
between 5 and 50 a negative test would be <5 or >50 
produces a the correct error message along with the correct 
handling process. A NORM condition should be created to 
verfiy and assure that the ages between 5 and 50 inclusive 
produces the correct response and process.