Effect occurs as solar radiation is absorbed by the earth’s surface and re-radiated into the atmosphere, where it gets trapped and warms the earth.

Greenhouse effect

Explanation:

Green house effect can be defined as the effect that occurs due to the absorption of radiant energy that is trapped in certain molecules in the atmosphere.

The greenhouse gases trap heat and radiates it within the thermal infrared range. These gases are carbon dioxide, methane, nitrous oxide ozone and water vapors.

Due to this the average temperature of earth is adequate for living.

the old price per ounce is c/4.

the new price per ounce is c/3.6.

the ratio of the old price to the new one is

(c/4)/(c/3.6) = (c/c)×(3.6/4) = 0.9 . . = 9/10 . . "nine tenths" in either form