This task is about writing a correct answer for the reading comprehension task. Based on the information provided in a given passage, you should identify the shortest continuous text span from the passage that serves as an answer to the given question. Avoid answers that are incorrect or provides incomplete justification for the question.

Q: Passage: Antibiotics are screened for any negative effects on humans or other mammals before approval for clinical use, and are usually considered safe and most are well tolerated. However, some antibiotics have been associated with a range of adverse side effects. Side-effects range from mild to very serious depending on the antibiotics used, the microbial organisms targeted, and the individual patient. Side effects may reflect the pharmacological or toxicological properties of the antibiotic or may involve hypersensitivity reactions or anaphylaxis. Safety profiles of newer drugs are often not as well established as for those that have a long history of use. Adverse effects range from fever and nausea to major allergic reactions, including photodermatitis and anaphylaxis. Common side-effects include diarrhea, resulting from disruption of the species composition in the intestinal flora, resulting, for example, in overgrowth of pathogenic bacteria, such as Clostridium difficile. Antibacterials can also affect the vaginal flora, and may lead to overgrowth of yeast species of the genus Candida in the vulvo-vaginal area. Additional side-effects can result from interaction with other drugs, such as elevated risk of tendon damage from administration of a quinolone antibiotic with a systemic corticosteroid. Some scientists have hypothesized that the indiscriminate use of antibiotics alter the host microbiota and this has been associated with chronic disease. Question: What is one possible serious side effect of over-using antibiotics?

A: alter the host microbiota
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Q: Passage: During the Second World War, General Dornberger was the military head of the army's rocket program, Zanssen became the commandant of the Peenemünde army rocket centre, and von Braun was the technical director of the ballistic missile program. They would lead the team that built the Aggregate-4 (A-4) rocket, which became the first vehicle to reach outer space during its test flight program in 1942 and 1943. By 1943, Germany began mass-producing the A-4 as the Vergeltungswaffe 2 ("Vengeance Weapon" 2, or more commonly, V2), a ballistic missile with a 320 kilometers (200 mi) range carrying a 1,130 kilograms (2,490 lb) warhead at 4,000 kilometers per hour (2,500 mph). Its supersonic speed meant there was no defense against it, and radar detection provided little warning. Germany used the weapon to bombard southern England and parts of Allied-liberated western Europe from 1944 until 1945. After the war, the V-2 became the basis of early American and Soviet rocket designs. Question: What was von Braun's role in the army's rocket program during during World War II?

A: technical director of the ballistic missile program
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Q: Passage: Economic conditions have started to improve considerably, after a period of stagnation, due to the adoption of more liberal economic policies by the government as well as increased revenues from tourism and a booming stock market. In its annual report, the International Monetary Fund (IMF) has rated Egypt as one of the top countries in the world undertaking economic reforms. Some major economic reforms undertaken by the government since 2003 include a dramatic slashing of customs and tariffs. A new taxation law implemented in 2005 decreased corporate taxes from 40% to the current 20%, resulting in a stated 100% increase in tax revenue by the year 2006. Question: What ws the overall impact to tax revenue from change of corporate tax rate?

A:
100% increase in tax revenue by the year 2006
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