用废旧报纸包装食品，会引起食品污染，这是由于印刷书报的油墨中含（ ） A．汞化合
题型：选择题
问题：
用废旧报纸包装食品，会引起食品污染，这是由于印刷书报的油墨中含（ ）
A．汞化合物
B．砷化合物
C．铅的有害物
D．铜的有害物
题型：选择题
阅读理解。
Gordon Williams's hobby may seem strange to people when they meet it for the first time. But it is a
traditional craft (手艺). He builds model ships inside old bottles.
Gordon has always loved ships, especially sailing ships from the old days. His interest in this hobby began
many years ago when he visited a museum in Ottawa, Canada, where there was a display of model ships in
bottles. Gordon thought the display was wonderful. But he wondered how the craftsman got the ship through
the thin neck of the bottle. Gordon decided to find it out.
He found an old master craftsman who was willing to teach him the necessary skills. First, Gordon takes
an old bottle. Then he puts in a layer of putty (一层油灰), carefully shaped and painted it look like the sea.
Next he builds the ship. To get the ship through the neck of the bottle, Gordon holds down the masts (桅杆).
Once the ship is inside the bottle, he takes a long, thin tool to raise the masts.
Gordon has completed well over one hundred models. His wish is to build bigger model ships, such as
aircraft carriers. This will be more challenging, as he will have to build the ship actually inside the bottle. His
hobby certainly needs time, patience and a steady hand.
1. What's their opinion when people first meet Gordon's hobby?
A. Useful.
B. Traditional.
C. Interesting.
D. Unusual.
2. How did Gordon become interested in this hobby?
A. He met a craftsman who would like to teach him.
B. He saw a show of model ships in bottles.
C. He had a journey to Canada.
D. He has collected many sailing ships.
3. For Gordon, the most difficult step that he wanted to learn was _______.
A. to shape the bottle like a ship
B. to paint the layer of putty like the sea
C. to get the ship through the neck of the bottle
D. to put the layer of putty into the bottle
4. Which of the following pictures shows the last step of Gordon's work?
5. Gordon's new plan is more challenging because he will _______.
A. build a bigger model ship inside the bottle
B. build more than one hundred ships
C. put a bigger model ship inside the bottle
D. make an aircraft carrier
的水平面上向右运动的物体，质量为20kg， 在运动过程中，还受到一个水平向左大小为10N的拉力作用，则物体受到滑动摩擦力为 N，方向 (水平向右或水平向左) 。