19.Which statement best describes the reaction taking place in the core of a star during its main sequence stage? a. Decay of carbon-14 to carbon-12
b. Fusion of hydrogen into helium
c. Fission of helium into hydrogen
d. Fusion of hydrogen into water vapor

10. translate each of the following chemical equations into a sentence. a. 2 zns(s) + 3 o2(g) -> 2 zno(s) + 2 so2(g) b. cah2(s) + 2 h2o(l) -> ca(oh)2 (aq) + 2 h2(g)

The difference between the atomic number of an element and the element’s atomic mass is the number of ions.

Diffraction is when light is bent around obstructions. which of the these observation about clouds would indicate diffraction? a) after rain storms, you can sometimes see rainbows. b) clouds are white or gray and cannot be seen through. c) on a cloudy day, the temperature tends to be cooler than a sunny day. d) the edges of dark clouds appear lighter. this