An atom has a mass number of 9 and 5 neutrons. What is its atomic number? OA. 14
O B. 11
OC. 4
OD. 19

4

Explanation:

It should be 4

The mass is 9

There are 5    neutrons

There are 9 - 5 = 4 protons

So it is the 4th element on the periodic table.

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:

bcde is the incorrect answer it is a