Why do some liquids form a convex surface when placed in a narrow test tube while others form a concave surface​

When a comet collides with earth, it adds material to our planet and causes great damage. therefore, a collision like this is a a. destructive force b. constructive force c. geologic process and event d. constructive and destructive force

Asolid that forms and separates from a liquid mixture is called

Which element has the lowest electronegativity? calcium(ca) gallium(ga) selenium(se) bromine(br)