What is the pH of a substance that has a hydrogen ion [H3O+] concentration of 5.01 x 10-9 M?

in cartography, a contour line (often just called a "contour") joins points of equal elevation (height) above a given level, such as mean sea level. a contour map is a map illustrated with contour lines, for example a topographic map, which thus shows valleys and hills, and the steepness or gentleness of slopes.

explanation:

listen, you cant how young you were.

"you didn't chose the stud life. the stud life chose you."