What are sound waves and how do they travel?

Which of the following true? a_volcanoes and earthquakes often near the plate boundaries. b_volcanoes occur whereve there are tall mountains. c_earthquakes cause volcanoes in the same location to erupt violently d_volcanoes and earthquakes occur only where plates are colliding with each other

Is this a single replacement reaction or there is no

If the atomic mass of an atom is 34 and the atom contains 13 protons, how many neutrons does the atom contain?