1. The forks shown are made of silver (Ag). Some of the silver forks shown have lost their luster—they have become tarnished. This is an
example of Type here.

Pleasee help

Corrosion

Explanation:

Silver is known as a noble metal. Noble metals are those metals that are resistant to corrosion.

However, we can not say that silver is completely resistant to corrosion because silver can corrode when exposed to air and sulphur.

Exposure to air and  sulphur leads to the coating of the silver with a sulphide layer thereby making the metal to become tarnished and loose its metallic luster.

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: