The nucleus contains 2 things. What are they? Group of answer choices

protons and nuetrons

2 nuetrons

2 eletrons

protons and electrons

Joseph has hypothesized that sound travels in waves. if he were following the scientific method, what should he do next? a. ask a question. b. test the hypothesis. c. study the results. d. tell other scientists about his hypothesis.

Which statement is true about this reaction? 14n+1h 15o it is a practical source of energy on earth. it occurs only outside the solar system. its product is heavier than each of its reactants. it shows the critical mass of an element.

Areaction in which products can react to re-form reactants is