Assuming that the variability in egg length for the cuckoo eggs data is the same for all host birds, obtain an estimate of the pooled standard deviation as a way of summarizing this variability....

Assuming that the variability in egg length for the cuckoo eggs data is the same for all host birds, obtain an estimate of the pooled standard deviation as a way of summarizing this variability. [Hint: Remember to divide the appropriate sums of squares by the number of degrees of freedom remaining after estimating the six different means.]