1.Two lots of rats were used in testing the effectiveness of a new serum in combating a certain disease. Both were inoculate with the causative organism, but only one lot was previously given the...

1.Two lots of rats were used in testing the effectiveness of a new serum in combating a certain disease. Both were inoculate with the causative organism, but only one lot was previously given the preventive serum. The results are below. Can anything be said abouttheeffectivenessoftheserum?Usealpha=0.01
                   Serum    NoSerum

Recovered     18          4

Died               4             8