The correct option is: c. contraction and tension during cooling of the flow
Explanation:
Columnar jointing is a geological structure that is formed in igneous rocks by <u>the cooling and contraction of the rocks and can also be formed in the cooling lava flows.</u> In this process, the columns or the polygonal prisms are formed by the intersecting, closely-spaced fractures called joints.
The columns formed can be straight or curved and 3 - 30 meters tall.
These joints on the basaltic rocks through occurring in moistly igneous rock types, created by lava and ash flow. Some Of the famous Columnar joints are found in places like Devil tower, Giant Causeway, and Deccan Traps, etc.
Upon cooling these forms These are arranged in regular angles and straight columns.
And the irregular array is termed as entablature. These condense to form various forms in nature through the cooling and spreading of lavas.
Manufacturing industries engage in production of goods (finished products) that have value in the marketplace service industries include those industries that do not produce goods and instead provide services
Radio waves are electromagnetic waves and as such travel at the speed of light. Waves emitted a century ago would be 100 hundred light years away. A light year is the distance light travels in one year. In one year light travels about 5.9 trillion miles. therefore the waves traveled about 590 trillion miles in a century.
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