1. [10 pts.] The element silicon (Si) has three naturally occurring isotopes, 28Si (atomic mass = 27.98 amu), 29Si (atomic mass 29.08 amu), and 32Si (atomic mass = 29.97 amu) with an average atomic mass of 28.09 amu. Silicon is 3.09 % 32Si. Calculate the percent relative abundance of 28Si and 29Si. 2. [15 pts.] An organic compound is composed of 61 % C, 4% H, and the rest is oxygen. If 0.109 moles of this organic compound have a mass of 15.0 g, what are the empirical and molecular formulas for this organic compound