Which of the following statements about heavy metals is true? A. Their specific gravity exceeds that of water by five or more times. B. None of them is necessary to sustain life. C. All of them are toxic even at trace levels. D. All of the above. E. None of the above.

Their specific gravity exceeds that of water by five or more times. (Ans. A)

Explanation:

Heavy metals are known as the element which can be two types one is present in the earth's shell and another is man-made sources. The chemical composition of heavy metals has a high density compared to water and low poisonous concentrations.

Some examples of these elements are lead, mercury, arsenic. Heavy metals consisting of elevated atomic weight with a certain gravity that helps to exceed the specific gravity of H2O by 5 or more times at 4°C temperature.

1. cold turkey (no outside ). about 90% of people who try to quit smoking do it without outside support -- no aids, therapy, or medicine. although most people try to quit this way, it's not the most successful method. only about 5% to 7% are able to quit on their own.

2. behavioral therapy. this involves working with a counselor to find ways not to smoke. together, you'll find your triggers (such as emotions or situations that make you want to smoke) and make a plan to get through the cravings.

3. nicotine replacement therapy. there are several types, including nicotine gum, patches, inhalers, sprays, and lozenges. they work by giving you nicotine without the use of tobacco. you may be more likely to quit with nicotine replacement therapy, but it works best when you use it with behavioral therapy and lots of support from friends and family. and remember that the goal is to end your addiction to nicotine, not simply to quit using tobacco.

explanation:

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