A manufacturer claims that the average tensile strength of thread A exceeds the average tensile strength of thread B by at least 11 kilograms. To test this claim, 52 pieces of each type of thread were tested under similar conditions. Type A thread had an average tensile strength of 85.7 kilograms with a standard deviation of 6.82 kilograms, while type B thread had an average tensile strength of 78.2 kilograms with a standard deviation of 6.06 kilograms. Test the manufacturer's claim using a 0.05 level of significance. Do not assume that the population variances are equal.

Let type A thread correspond to population 1 and let type B thread correspond to population 2. Identify the null and alternative hypotheses. Choose the correct answer below.

A.H0:μ1−μ2=11H1:μ1−μ2≠11.
B.H0:μ1−μ2≠11H1:μ1−μ2=11.
C.H0:μ1−μ2=11H1:μ1−μ2>11.
D.H0:μ1−μ2<11H1:μ1−μ2=11.
E.H0:μ1−μ2=11H1:μ1−μ2<11.
F.H0:μ−μ2>11H1:μ1−μ2=11.

Identify the critical region. Select the correct choice below and fill in the answer box(es) to complete your choice. (Round to two decimal places as needed.)