Please help me with this question i am timed
please find the value of u.

Researchers were interested in whether relaxation training decreases the number of headaches a person experiences. they randomly assigned 20 participants to a control group or a relaxation training group and noted the change in number of headaches each group reported from the week before training to the week after training. which statistical analysis should be performed to answer the researchers' question?

1mile equals approximately 1.6 kilometers. which best approximates the number of miles in 6 kilometers?

Three times the sum of a number and seven is negative thirty-six. what is the number?