Pollutants also affect the atmosphere through their contribution to global warming. Global warming is an increase in the Earth's temperature. It is thought to be caused mostly by the increase of greenhouse gases like carbon dioxide. Greenhouse gases can be released by factories that burn fossil fuels. Over the past 20 years, burning fossil fuels has produced about three-quarters of the carbon dioxide from human activity. The rest of the carbon dioxide in the atmosphere is there because of deforestation, or cutting down trees ( Figure below ). Trees absorb carbon dioxide during cellular respiration, so when trees are cut down, they cannot remove carbon dioxide from the air. Long island was full of people and they used all their natural resources and burned fossil fuels while Snail island protected the environment and had fewer people living there. Which island contributed less to an increase in Earth's temperature?
Ans: Snail

Some mutations have a positive effect on the organism in which they occur. They are called beneficial mutations . They lead to new versions of proteins that help organisms adapt to changes in their environment. Beneficial mutations are essential for evolution to occur. They increase an organism's changes of surviving or reproducing, so they are likely to become more common over time. There are several well-known examples of beneficial mutations. Here are just two: A sudden climate change hits Alaska and it starts to become warmer. As a result many species of mammals have started to adapt to the warmer climate and now grow less fur. Will the adaptation of growing less fur in a warmer environment increase or decrease the chances of these mammals reproducing?
Ans: increase

The Hawaiian Islands ( Figure above ) are in the central Pacific Ocean. The islands are volcanoes that increase in age from southeast to northwest. The youngest island is the Big Island of Hawaii at the southeast end of the chain. The volcanoes get older through Maui, Kahoolawe, Lanai, Molokai, Oahu, Kauai, and Niihau Islands through the northwest. The Kilauea volcano on Hawaii has been erupting almost continuously since 1983. There are also eruptions at an underwater volcano called Loihi seamount. Loihi is the youngest volcano. Hawaii is a fantastic place to see volcanic eruptions and features. Two old friends Mary and Ann lived thousands of miles away. Mary lived on the Big Island of Hawaii, while Ann lived in Boston. Mary visited Boston, while Ann has never been to Hawaii. Which friend never visited Kauai Island?
Ans: Ann

East Antarctica is colder than its western counterpart because of its higher elevation. Weather fronts rarely penetrate far into the continent, leaving the centre cold and dry. Despite the lack of precipitation over the central portion of the continent, ice there lasts for extended periods. Heavy snowfalls are common on the coastal portion of the continent, where snowfalls of up to 1.22 metres (48 in) in 48 hours have been recorded. Joe lived in East Antarctica while his buddy Jim lived in West Antarctica. They were both into collecting rare specimens of plants and wildlife. They would often complain about the weather. Which friend experienced more precipitation?
Ans: Joe