Once a month, just after sunset, trucks fill an outdoor parking lot in Los Angeles, California．Some trucks sell all kinds of food. Others have clothing for sale. These are known as fashion（时尚）trucks.
It's really fun to go through everything in the truck. The back of the truck is a small store. Clothing hangs on one side. Jewelry（首饰）and purses are on the other. The store looks colorful and is well organized. There is also a very small room for trying on clothes.
Jordana Fortaleza is one of the truck owners. She says the cost of owning a truck is much lower than paying for a store. And there is another reason to use a truck. You can take your business to your customers. But there are also difficulties.
The biggest problem is the weather. In winter, it's cold outside and there's no one around. Another problem is keeping the truck in good condition. When it breaks down, the repairs can take days. Business stops during the time. It happens at least once a year because her truck is 38 years old．
Meagan Rogers is a fashion school graduate. She says the job market is so hard now, but with a fashion truck she's able to start earning money while her classmates are still working without pay.
Which of the following is an advantage of a fashion truck?（ ）
事实细节题。由第三段第二句可知，一辆时尚货车的花费要比一间店铺的花费低得多。这正是时尚货车的优点之一。故B正确。
把10gMgCl2和MgSO4的混合物溶于适量水中，滴加2mol／L的BaCl2溶液至沉淀完全，共消耗BaCl2溶液25mL。求混合物中MgCl2和MgSO4的质量各是多少克
固定在匀强磁场中的正方形导线框abcd，各边长为1．其中ab是一段电阻为R的均匀电阻丝，其余3边均为电阻可忽略的铜线。磁场的磁感应强度为B，方向垂直纸面向里。现有一与ab段的材料、粗细、长度都相同的电阻丝PQ架在导体框上，如图所示。PQ以恒定速度方向如何
一小物块以速度v0=10m／s沿光滑地面滑行，然后沿光滑曲面上升到顶部水平的高台上，并由高台上飞出，如图所示。问当高台的高度h多大时，小物块飞行的水平距离最大这个距离是多少(g=10m／s2)
某晶体盐的水溶液呈浅绿色，在此溶液中通入氯气，溶液变为棕黄色，把所得棕黄色溶液分成两份：一份加入KSCN溶液，溶液变深红色；另一份加入BaCl2溶液，产生不溶于稀HNO3的白色沉淀，则该晶体盐的化学式是_______。
欲除去乙烷中的乙烯，可将混合气体通过盛有_______的洗气瓶；欲除去乙炔中的硫化氢，可将混合气体通过盛有_______的洗气瓶。
浓硝酸常盛装在棕色瓶中，且贮放在冷暗处，原因是_______，
碳酸氢钠溶液和烧碱溶液反应的离子方程式为_______。
常温下，氨水中存在的离子有_______。
在酸或碱存在的条件下，甲酸甲酯跟水发生水解反应的化学方程式为_______。
有下列几种气体：H2、O2、HCl、NO、NH3、CH4，其中通常情况下能用来和水做“喷泉”实验的是_______。
