Combing your hair leads to excess electrons on the comb. How fast would you have to move the comb up and down to produce red light

What is the formula for calcium iodide

Melting and boiling are endothermic processes. this means that these processes absorb energy from their surroundings in order to occur. use this information and the data you collected in the phase change gizmo to describe what happens to the temperature of water when you boil it, then explain why this result occurs.

Stage in which a star’s outer layers have started to cool and grow outward?