It is believed that animals living in eastern regions have shorter appendages than animals living in western regions. Random samples of birds were selected from each group and wing lengths for birds (in millimeters) were measured. The following table gives summary statistics.

Region: n, Average, Standard Deviation

Eastern (E): 31, 115.6, 1.5

Western (W): 31, 116.3, 3.4

Difference (d = N - S): 31, -0.7, 1.4

(a) Find a 90% confidence interval for the mean difference of wing lengths of birds between the Eastern regions and the Western regions. (Round your answers to 4 decimal places, if needed.)

(b) Based on this confidence interval, is there enough evidence to support the belief?

No, since the interval is completely below 0.

No, since the interval contains 0.

Yes, since the interval contains 0.

Yes, since the interval is completely below 0.