I need help with these two please

For which pair of functions is (gof)(a)=|a|-2?

Acircle has a radius of 5/6 units and is centered at (3.6, 7.8) write the equation of this circle

Recall that the owner of a local health food store recently started a new ad campaign to attract more business and wants to know if average daily sales have increased. historically average daily sales were approximately $2,700. the upper bound of the 95% range of likely sample means for this one-sided test is approximately $2,843.44. if the owner took a random sample of forty-five days and found that daily average sales were now $2,984, what can she conclude at the 95% confidence level?