Grandma has 250,000 to invest. She divides her money into two accounts. One account is in ultra-safe treasury bills paying 4% interest, and the other is in riskier corporate bonds paying 6%. If she needs 12,000 per year in income from her investment, how much should she invest in each account? SHOW YOUR WORK

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?