Also is it normal for hair to fall out if they don't have enough vitamin d?

Nuclear fusion is the source of energy for stars. besides hydrogen, which other element is most likely also common in stars?

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

When balancing a chemical equation: