Two surgical procedures are widely used to treat a certain type of cancer. To compare the success rates of the two procedures, a random sample from each type of procedure is obtained, and the number of patients with no re-occurrence of the disease after 1 year was recorded. Here is the data.

Procedure	n	No Re-Occurrence
A	100	78
B	120	102

Find a 90% confidence interval for the difference in success rates.

Select one:

a.

-0.07 0.087 = (-0.157,0.017)

b.

0.07 0.059 = (0.011, 0.129)

c.

0.07 0.0054 = (0.0646, 0.0754)

d.

-0.07 0.103 = (-0.173, 0.033)