500
A new element has been discovered! It has 7 isotopes that we know of so far. Scientists want to know what the atomic mass should be for this element. The masses of the isotopes are 120 amu, 121 amu, 122 amu, 119 amu, 117 amu, 130 amu, and 137 amu. This is the atomic mass for the new element. Include the proper unit!!!
What is the average of all of the masses of the isotopes: 123.71 amu?