Acollege friend of yours who has been postponing taking any science courses hears you talking about the generation of nuclear energy in the sun and makes the following observation: "the whole idea of the atomic nucleus is pretty ridiculous. if an oxygen nucleus consists of eight protons and eight neutrons, the charge on that nucleus is positive. since even i learned in high school that like charges repel, such a nucleus would find all its positive protons repelling and quickly fall apart." how would you answer his argument?