I give brainliest! A person is going 80 miles per hour. How long does it take for the person to go 80 miles?

Write numerical coefficient of y² in the expression 2x² - 15xy – 7y²

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?

Given a: b and b: c, find a: b: c. write the ratio in simplest form. a: b=6: 10 and b: c=21: 33