Select all of the things are done to boats, cars, and planes in order to reduce friction.
the surface is polished.
the body is streamlined.
special rivets are added.
they are built with sleek, tapering lines.

This classification of drug typically changes the brain's chemistry and reduces its ability to create its own endorphins.

13. a covalent bond between two atoms is likely to be polar if: a. one of the atoms is much more electronegative than the other. b. the two atoms are equally electronegative. c. the two atoms are of the same element. d. the bond is part of a tetrahedrally shaped molecule. e. one atom is an anion.

An alloy contains 66 g of pure zinc. what is the percentage of zinc in the alloy? express your answer to two significant figures and include the appropriate units.