For the data in the following matrix:             No trx         Treatment

Male   M=5             M = 3                  Overall M = 4

Female M = 9         M =13                Overall M = 11

Overall M = 7         Overall M = 8

a) which two means are compared to describe the treatment main effect?

b.) which two means are compared to describe the gender main effect?

c. ) Is there an interaction between gender and treatment? Please explain answer.