cnumbers.zip  Evaluate complex number expressions.
jkcalc.zip    Multi-purpose calculator works also with polynomials.
precalcx.zip  Professor Weissman's Pre-Calculus Tutorials
rurca.zip     Quizzes students on topics needed to take coll. alg.
ruria.zip     Quizzes students on topics needed to take inter. alg.
tsdraw16.zip  Graphical solution of lin. prog. in 2 dimensions.