Use the Following Information for Questions:
a Researcher Wants $µ_1$

Multiple Choice

Use the following information for questions:
A researcher wants to assess if there is a difference in the average life spans between men and women in Japan. Let $µ_1$ = average life span of Japanese women and $µ_2$ = average life span of Japanese men. A random sample of 10 women showed an average lifespan of 83 years, with a sample standard deviation of 7 years. A random sample of 10 men showed an average lifespan of 77 years, with a sample standard deviation of 6.4 years. Assume that life spans are normally distributed and that the population variances are equal.
-What is the value of the test statistic?

A) t = 1.65
B) t = 1.80
C) t = 2.00
D) None of the above