17.food that is both nutrient- and calorie-dense can be a good choice in what circumstance? A. When it is high-glycemic
B. When it contains trans fats
C. When it contains more than 400 calories per serving
D. When it is portion-controlled

The experiment done in lab is repeated, using a ball that has unknown mass m. you plot your data in the form of f 2 versus m/l, with f in rev/s, m in kg, and l in m. your data falls close to a straight line that has slope 3.19 m/(kg · s2). use g = 9.80 m/s2 and calculate the mass m of the ball.