It used to take Redwood City, California police hours to locate gunfire. Now, they have a new tool that helps them find the gunfire quickly. This new tool is called the ShotSpotter. The police began using the ShotSpotter in 1995. They wanted to cut down on gunfire in their city.
One ShotSpotter covers a square mile. Eight microphones are put on the roofs of buildings. These microphones pick up gunfire noise. It only takes seven seconds to report the gunfire to the police. Then a red dot on the police map shows where the action is.
The ShotSpotter really works well. It locates the gunfire within 20 to 40 feet plus or minus. Redwood City police are very happy with the ShotSpotter. They think it might have helped catch the D.C. sniper.
ShotSpotters cost a lot of money. One of them sells for $200,000. Despite the cost, ShotSpotters can be a big help in fighting crime.
The tanker lay in the bay for four days, a few hundred meters from the shore. In this tideless water she lay as still and secure as if fastened to a wall. In a way, she was, for the sandy bottom held her in its grip. Twice the harbor master’s boat went out to her; the second time it brought off a number of the crew. It never occurred to the watchers on shore that the ship was in danger. She looked so calm and seaworthy. From time to time there was activity on board: When a land wind rose in the evenings, the tanker’s engines came to life. Then the vessel shook herself and strained fiercely, but none of it did her any good. She just stayed where she was in the bay.
The July sun blazed down on her flat decks. Occasionally a seaman, stripped to the waist, came out on to the deck with the movements of someone performing a complicated dance, stepping lightly, never resting on that burning metal. Once or twice he kept close to the ship’s rail, with an arm rais
A. offered to help without knowing what to do
B. did not know there was something wrong with the ship
C. realized the trouble but could do nothing about it
D. did not want to put themselves in any danger
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