I need help please it says,"On Monday at 1 p. m., when the ocean’s surface was at an elevation of 2.2 feet, Winston went to a surf shop that was 8.2 feet above the ocean’s surface. At 7 p. m. when the ocean’s surface was at an elevation of -2.4 feet, Winston ate dinner at a restaurant whose deck was 10 feet above the ocean’s surface. How many feet apart are the two ocean elevations described in part A?"

The students at jefferson middle school are raising money for a charity by selling t-shirts and hats. the number of t-shirts sold was 3 times the number of hats. the profit was $5 for each t-shirt sold and $2.50 for each hat sold. the students raised $840 for the charity. they used the system below to analyze their success and found the solution to be (144, 48). 5x+2.50y=840 x=3y how much did they earn from t-shirt sales?