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Mercury, also known as quicksilver, is one of the few elements that are in liquid form at room temperature. Over the centuries mercury has had many ritualistic and scientific uses, almost all of which have been discontinued as its toxic properties have come to be understood.  In ancient China and India, mercury was considered an aid to good health. Historians believe that an early Chinese emperor was driven insane and killed by mercury pills that were supposed to make him live forever.  In Europe and America in the 1700s and 1800s, mercury was used in the manufacture of felt for making hats. The mercury solutionthat the hat makers used was highly toxic. Symptoms included hallucinations and dementia—thus the origin of the phrase “mad as a hatter.” Mercury was once widely used to treat syphilis, which caused confusion because mercury poisoning symptoms are so similar to those of the disease it was supposed to relieve. It was also used as a diuretic and as a laxative.  Although now banned in the United States, mercurochrome is still widely used around the world as a topical antiseptic. Mercury’s use has been discontinued in home thermometers, herbicides, and light switches. Through its industrial uses it has entered thefood chain, showing up in potentially dangerous concentrations in some kinds of fish. Mercury is still used in dentistry. Although mercury amalgam fillings are still officially considered safe for humans, this usage has become controversial.   Which of the following sentences is the main ide?

In 1962 biologist Rachel Carson published Silent Spring, a powerful dissection of the ways that pesticides, particularly DDT, were poisoning man and nature.  In 1972, the federal government banned DDT, largely _______________________ of the outcry that Carson’s book had raised.

Fill in each blank with an appropriate transition from the box. Use each transition once.  

Lighting levels add meaning to communication messages.  In lecture halls and reading rooms, bright light is expected—it encourages good listening and comfortable reading.________________________, in a chic restaurant, a music listening room, or a television lounge, you expect the lighting to be soft and rather dim, which makes for a cozy atmosphere that invites intimate conversation.

The sentence–Front steps facing the sidewalk are places for neighbors to sit and visit, just as corners are places to “hang out.”– is a 

One transition that signals the pattern of organization of this paragraph is ______________.

The sentence–One such pattern is withdrawal, the physical or psychological removal from a conflict situation.– provides

How many major supporting details are in this reading passage?

An airplane is supported in flight by air passing across its wings. Air traveling over the wings moves farther and faster than air traveling under the wings.  As a result, the air pressure is lower above the wings, and the wings experience an upward lift force.  This lift force decreases at low airspeeds, so most commercial jet airplanes must alter the shapes of their wings during takeoffs and landings.   The pattern of organization is ______________.

The colonists rebelled against the imposition by the British government of which of the following?