add > (ogt, o greater than) Chap04 p74 L2
modify > (ogt, o greater than) Chap04 p75 L7
add < (olt, o less than) Chap04 p75 L11
add oeq = Chap04 p76 L1 (left)
modify oeq (=) Chap04 p76 L1 (right)
add oexpt (o expt) Chap04 p76 L6
add oquotient Chap04 p77 L4