) Ionic bonds:- a) Are formed in the reaction of an atom of low ionization potential with an atom of high electron affinity.

b) Are sometimes called electro vale bonds.

c) Are generally formed by reaction between alkali metals with halogens.

d) a & b & c. e) a & b

The answer is e

Explanation:

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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:

the correct answer is:

a. formation of precipitation