Composition of Earth's atmosphere by volume. The lower pie represents the trace gases that together compose about 0.038% of the atmosphere (0.043% with CO 2 at 2014 concentration). The numbers are from a variety of years (mainly 1987, with CO 2 and methane from 2009) and do not represent any single source.
Dominance and submission (also called D/s) is a set of behaviors, customs, and rituals involving the submission of one person to another in an erotic episode or lifestyle. It is a subset of BDSM. Physical contact is not necessary, and D/s can be conducted anonymously over the telephone, email, or other messaging systems.
This is called a direct relationship. (In an equation such as Y = -X, the relationship is still direct, although Y decreases as X increases, because X1/X2 = Y1/Y2) One way to picture this relationship that doesn't involve any math is to think about a seesaw or teeter-totter that is in balance with one child on each end.