State two factors that determine the stability of isotope​

Three cards with holes are arranged in a straight line. a light is shined through the first card’s hole and travels through all three cards. what does this tell you about light rays? a) that light is reflected b) that light is refractive c) that light travels in a straight line d) that light does not travel in a straight line

Exit what is the density of an object having a mass of 5.0 g and a volume of 45.0 cm3?

Suppose you discovered a new element with 120 protons and 2 electrons in its outer level . i'm what group does this new element belong? what properties would you expect it to have