Provide an example of how a genetic mutation could be positive, then explain how that mutation could cause a change in a population over time ​

Covalent network solids typically have melting points and boiling points. the chemical formula of a network solid indicates in the molecule.

When a spring is compressed, the energy changes from kinetic to potential. which best describes what is causing this change?

Modern pennies are composed of zinc coated with copper. a student determines the mass of a penny to be 2.482 g and then makes several scratches in the copper coaling (to expose the underlying zinc). the student puts the scratched penny in hydrochloric acid, where the following reaction occurs between the zinc and the hcl (the copper remains undissolved): zn(s) + 2 hcl(aq) → h2(g) + zncl(aq)the student collects the hydrogen produced over water at 25 °c. the collected gas occupies a volume of 0.899 l at a total pressure of 79 j mmhg. calculate the percent zinc (by mass) in the penny. (assume that all the zn in the penny dissolves.)