What mechanical waves needs a medium to travel through?

a. all mechanical waves need a medium to travel through
b. surface waves only
c. transverse and longitudinal waves only
d. longitudinal and surface waves only

The melting point of sulfur is 115 °c and its boiling point is 445 °c. what state would sulfur be in at 200 °c?

How many moles of potassium hydroxide are needed to completely react with 2.94 moles of aluminum sulfate

Astable electron arrangement for an atom is one that does not easily change. how is this arrangement arrived at? a. valence electrons are transferred or shared to create a full outer shell of electrons. b. valence electrons are discarded into space to create a full outer shell of electrons. c. protons (positive charge) pair with valence electrons (negative charge) to create a strong bond. d. outer shells with valence electrons are transferred or shared.