Problem: Keith was reading a book on climate. He found an interesting table that showed the climatic conditions of the earth in two different times, time A and time B. Time A showed earth's climatic condition in the previous century. And, time B showed earth's climatic condition in the present century. Keith was amazed to see how the world has changed in just a century. Which period would see higher average temperature, time A or time B? Hint: Another major cause of extinction is global warming , which is also known as global climate change. During the past century, the Earth's average temperature has risen by almost 1C (about 1.3F). You may not think that is significant, but to organisms that live in the wild and are constantly adapting to their environments, any climate change can be hazardous. Recall that burning fossil fuels releases gasses into the atmosphere that warm the Earth. Our increased use of fossil fuels, such as coal and oil, is changing the Earth's climate. Any long-term change in the climate can destroy the habitat of a species. Even a brief change in climate may be too stressful for an organism to survive. For example, if the seas increase in temperature, even briefly, it may be too warm for certain types of fish to reproduce.

A: time B

Problem: The doctors studied two groups of people, group one which included people with respiratory diseases caused by viruses, and group two, which had people with respiratory diseases caused by bacteria. Which group didn't include people that had the common cold? Hint: Many respiratory diseases are caused by pathogens. A pathogen is an organism that causes disease in another organism. Certain bacteria, viruses, and fungi are pathogens of the respiratory system. The common cold and flu are caused by viruses. The influenza virus that causes the flu is pictured below ( Figure below ). Tuberculosis, whooping cough, and acute bronchitis are caused by bacteria. The pathogens that cause colds, flu, and TB can be passed from person to person by coughing, sneezing, and spitting. Illnesses caused by bacteria can be treated with antibiotics. Those caused by viruses cannot.

A: group two

Problem: Dan decided to preserve some fruit and roots to see how long they last before they spoil. He also bought other fruit that he plans to eat fresh. He candied plums, pears, ginger and quince, and he ate fresh apples, oranges and mango. Which fruit have a higher sugar content candied plums or fresh apples? Hint: Candied fruit, also known as crystallized fruit or glace fruit, has existed since the 14th century. Whole fruit, smaller pieces of fruit, or pieces of peel, are placed in heated sugar syrup, which absorbs the moisture from within the fruit and eventually preserves it. Depending on size and type of fruit, this process of preservation can take from several days to several months.[1] This process allows the fruit to retain its quality for a year.[2] The continual process of drenching the fruit in syrup causes the fruit to become saturated with sugar, preventing the growth of spoilage microorganisms due to the unfavourable osmotic pressure this creates.[3]

A: candied plums

Problem: Two sister cities were both situated on plate boundaries, close to volcanoes, on different continents. Red city was 10 miles from a volcano, while Tree city was 60 miles away. Red city experienced many earthquakes, Tree city few and far between. Which city experienced the release of energy that was stored in the rocks less often? Hint: Almost all earthquakes occur at plate boundaries. All types of plate boundaries have earthquakes. Convection within the Earth causes the plates to move. As the plates move, stresses build. When the stresses build too much, the rocks break. The break releases the energy that was stored in the rocks. The sudden release of energy creates an earthquake. During an earthquake the rocks usually move several centimeters or rarely as much as a few meters. Elastic rebound theory describes how earthquakes occur ( Figure below ).

A:
Tree