Aperson's protein requirement is the amount of protein they must consume in a day to maintain a stable weight, muscle mass, etc. a group of researchers wanted to know if the mean protein requirement (in grams of protein per day per kg of body weight) is the same for young adult males and females. the protein requirements of 12 males and 11 females was determined and presented: males females0.74 0.820.76 0.800.59 0.680.44 0.510.46 0.540.51 0.630.63 0.700.29 0.800.43 0.490.59 0.740.47 0.620.72a) is this a designed experiment or observational study? justify your answer. b) construct a 99% confidence interval for the difference in mean protein requirement of young adult males and females. assume that the populations are normally distributed.