6. The difference between the groups is:

(a) Unlikely to have occurred by sampling error, assuming the null hypothesis to be true (F (2,470) =

387.806; p 60.001)

(b) Unlikely to have occurred by sampling error, assuming the null hypothesis to be true (F (2,470) =

14.565; p 60.001)

(c) Likely to have occurred by sampling error, assuming the null hypothesis to be true (F (2,470) =

387.806; p 60.001)

(d) Likely to have occurred by sampling error, assuming the null hypothesis to be true (F (2,470) =

14.565; p 60.001)