A Company Conducted an Experiment to Investigate the Effects of Three

Multiple Choice

A company conducted an experiment to investigate the effects of three different processes on the strength of its steel. The investigators randomly divided the production of 120 batches of steel, using 40 batches for each process. The steel was rated on a scale of 0 to 100 for its strength. The following sample means and standard deviations were obtained. The degrees of freedom for the F test are:

A) 3, 117.
B) 3, 120.
C) 2, 40.
D) 2, 117.