Which of the following are lost or gained during a nuclear reaction?

a) electrons and nucleus
b) electrons and neutrons
c) protons and electrons
d) protons and neutrons

Sum of brother and sisters age is 26. four times the brothers age is subtracted from three times the sisters age, the difference is 8. what are the ages of the brother and sister?

What is the common name for the compound shown here? enter the common name of the compound shown?

Which best describes the present-day universe? opaque, expanding very slowly, stars produce heavy elements transparent, expanding at an accelerated rate, stars produce heavy elements opaque, expanding at an accelerated rate, stars produce only hydrogen and helium transparent, expanding very slowly, stars produce only hydrogen and helium