Are you asking us to do your homework? This is not a homework list. For the t-test look in any introductory R manual. For the histograms, look in the lattice library. HTH Daniel -- View this message in context: http://r.789695.n4.nabble.com/More-complex-historgram-tp2197823p2216076.html Sent from the R help mailing list archive at Nabble.com.