If the mass of an object is 15 grams then determine the relative precision and accuracy for the following sets of measurements
1. 15.1 g, 15.2 g, 15.1g, 15.1 g
2. 16 g, 14 g, 14 g, 16 g
3. 19.1 g, 16.0 g, 22.4 g, 23.8 g
4. 15.1 g, 14.9 g, 15.0 g, 15.0 g