Timed Scanning/Skimming Practice 8 - 4 Questions in 3 Minutes.

DIRECTIONS:
THE QUESTIONS IN THIS PRACTICE SET ARE ALL FACTUAL; THEY CAN BE ANSWERED BY MERELY SCANNING THE PASSAGE BELOW LOOKING FOR CLUE-WORDS FROM THE QUESTIONS.
IF IT IS YOUR STRATEGY TO READ THE QUESTIONS BEFORE READING THE PASSAGE YOU CAN DO THAT IN THIS ACTIVITY. JUST SCROLL TO THE BOTTOM OF THIS PAGE AND CLICK START NOW.
IF IT IS YOUR STRATEGY TO READ OR PREVIEW THE PASSAGE BEFORE LOOKING AT THE QUESTIONS, YOU MAY DO SO NOW.

Silk is the strongest natural fiber known to humans. Fabric using this fiber first appeared in ancient China, possibly as early as 6000 BCE. Its luminous appearance comes from tiny triangular structures within the fibers, resembling prisms, which refract light from various angles.

The most common silk fiber comes from cocoons formed by the larvae of Bombyx mori silkworms. These small creatures are bred in captivity and are no longer found in the wild. The larvae enclose themselves in a cocoon of raw silk produced in their salivary glands that provides protection during their vulnerable, almost motionless pupal state. If a silkworm survived after spinning its cocoon it would soon create a hole while exiting as a moth. This would cut short and damage the silk threads; consequently, when it comes time to harvest the cocoons, they are tossed into boiling water to kill the worms and make the silk easier to unravel. The silkworms are later eaten as a delicacy.

An average, undamaged, silkworm cocoon produces a continuous thread of raw silk 1000 to 3000 feet (or 2/3 of a mile) long, Theoretically, ten unraveled cocoons could extend vertically to the height of Mt. Everest. It takes about 2,000 to 3,000 cocoons to produce one pound of silk. It is estimated that 70 million pounds of raw silk are produced each year; this equals 70 billion miles of silk filament, enough cover the distance of over 300 round trips to the sun.