C105 E1 SPRING 2015.LXRTESTAn imaginary element wazzunium (Wz) consists of two naturally occurring isotopes: 70Wz has an isotopic mass of 69.9243 amu and74Wz has an isotopic mass of 73.9219 amu. The atomic mass of wazzunium is 72.6394 amu. What is the % natural abundance of 74Wz?