English Placement Test

Big Screen Secrets We've all watched movies in which people get in fights and crash through windows, shattering the glass all around them. Did you ever wonder why the actors don't get hurt? It's not real glass! Instead, filmmakers use sugar glass—sugar candy that has been molded to look like regular glass. Both types of "glass" are made using similar processes. Several ingredients are combined and heated until the mixture undergoes a chemical change, making the mixture transparent and allowing it to hold a shape when it cools. So, when movie directors use film props made out of sugar glass, they get the look and sound of real glass breaking, but with less danger because it is not as hard as real glass. It's also cheaper, which is important if a scene has to be filmed several times. Unfortunately, there are limitations to the use of this special glass. If it is not used shortly after it's made, it gets soft and sticky. Additionally, sugar glass cannot be used in scenes that involve water or heat because it will melt.

The Rise of the Pine Beetle In the forests of western North America, the mountain pine beetle has a powerful impact on its environment. The little bug is responsible for killing millions of acres of trees every year from northern Canada all the way south to New Mexico. The pine beetle is such a severe threat to trees because it attacks on two fronts. There is the beetle infestation itself, whereby the beetles bore into tree trunks and eat the inner bark of the tree. Then in addition to this physical attack, the mountain pine beetle also transmits a fungus to the trees, called bluestain fungus. This fungus grows within the tree and assists the beetle in killing it. The mountain pine beetle lives for 12 months. Each adult female beetle lays about 75 eggs under the bark of a tree. After they hatch, the larvae spend 10 months feeding under the bark. Then, usually around July or August, the larvae transform into adult beetles and leave the tree they had been living in to attack other trees. The trees most likely to be attacked are old ones and weakened trees, such as those that experience crowded growing conditions and trees that have been damaged by fire. To make matters worse, periods of above-average temperatures have contributed to the spread of the damaging insect. It takes several weeks of temperatures at or below freezing to kill off the beetles. The western mountain regions of Canada and the United States used to experience such lengthy spells of cold weather every winter, but that is changing. Once a tree has been infested by the pine beetle there is virtually nothing that can be done to save it, so the forests of western North America are under serious threat.