question 9\n5 pts\nwhat are the ideal mass numbers for carbon and boron\n8 and 16\n6 and 5\n12 and 10\n10…

Brief Explanations:

The mass number of an element is the sum of protons and neutrons in its nucleus. Carbon has 6 protons and 6 neutrons in its most common isotope, giving it a mass - number of 12. Boron has 5 protons and 5 neutrons in its most common isotope, resulting in a mass - number of 10.

Answer:

C. 12 and 10