Statistics

. A researcher believed that there was a difference in the amount of time boys and girls at 7th grade studied by using a two-tailed t test. Which of the following is the null hypothesis?

a. Mean of hours that boys studied per day was equal to mean of hours that girls studied per day

b. Mean of hours that boys studied per day was greater than mean of hours that girls studied per day

c. Mean of hours that boys studied per day was smaller than mean of hours that girls studied per day

d. Mean of hours that boys studied per day was smaller than or equal to mean of hours that girls studied per day

Answer#1# a