Read the article and select the best answer. Article: People born in winter are more likely to suffer mental health disorders, according to a recent study carried out by researchers at Vanderbilt University in Tennessee. Researchers raised baby mice from birth to weaning in either "summer" light cycles of 16 hours of light and 8 hours of dark or "winter" cycles of 8 hours of light and 16 hours of dark. A third group experienced 12 hours of light and 12 hours of dark a day. Then half the winter mice stayed in a winter cycle, while half switched to a summer schedule. The summer mice were similarly _ . The mice raised in equal periods of light and dark were split into three groups, one of which stayed on the 12hour schedule, one of which joined the winter group, and one of which joined the summer group. After 28 days, it turns out the summerborn mice behaved the same whether they stayed on the summer cycle or switched to winter. But among the winterborn mice, those stayed in winter kept their previous schedule, while those that switched to summer stayed active for an extra hour and a half, which indicates that mice born and weaned in a winter light cycle showed dramatic disruptions in their biological clocks. The finding is the first of its kind in mammals, and it could explain why people born in winter are at higher risk for mental health disorders including bipolar depression, schizophrenia and seasonal affective disorder. "We know that the biological clock regulates mood in humans,"said study researcher McMahon. "If the mechanism similar to the one that we found in mice operates in humans, then it could not only have an effect on a number of behavioral disorders, but also have a more general effect on personality." Question: How many groups of mice are there finally in all in the experiment? Options: A: Four. B: Five. C: Six. D: Seven.
D

Read the article and select the best answer. Article: New software is able to analyze exactly how many hairs there are in a patch of skin and could help in testing the effectiveness of baldness treatments and depilatory creams, say Australian researchers. Researchers from CSIRO Mathematical and Information Sciences in prefix = st1 /Sydneyreport their findings in the November issue of the journalSkin Research and Technology. The software, developed with a UKcompany, will make it easier for researchers developing hair removal creams to accurately assess how well they work, says Dr Pascal Vallotton. "Up to now they were counting the number of hairs that survived after treatment by hand. That's hard work and it's difficult because you may count a hair twice or you may miss it." he said. The software relies on images captured by a small flatbed scanner pressed onto the skin. Using a mathematical algorithm , the software then identifies and traces each individual hair based on an understanding of a hair's unique features, such as its straightness. The software is able to distinguish between hairs and other features on the skin such as wounds or moles . "Our skin irregularities make it difficult to say this is a hair or this is a mole," Dr Vallotton said. Comparison between earlier and later images can also determine if hair is growing quickly or slowly, he says. Unfortunately, to check the accuracy of the software, the researchers still had to adopt the old-fashioned method of counting hairs, helped by volunteers from neighboring labs who put their skins on the line for science. "We had 12 volunteers, mostly from neighboring labs, and we acquired images of hair before and after treatment," Dr Vallotton said. To ensure an accurate count, the individual hairs had to be marked off as they were counted, but after such a laborious process, the researchers were pleased to discover the software results were comparable to the manual count. Dr Vallotton says the software could also be useful in testing the effectiveness of balding treatments and counting or tracing... Question: Which is the best title of the text? Options: A: Do you think it is possible to count hairs? B: New software makes counting hairs easy. C: Australians find new treatments for baldness. D: New software is found in BritainandAustralia.
B

Q: Read the article and select the best answer. Article: You know that balloons must be kept away from sharp objects. They also needed to be kept away from flames. A fire can weaken the rubber and cause it to break. However, in this experiment you will find out how you can hold a balloon directly in a flame without breaking the balloon. Materials needed: * two round balloons not inflated * several matches * water Inflate one of the balloons and tie it. Place 1/4 cup of water in the other balloon, and then inflate it and tie it. Light a match and hold it under the first balloon. Allow the flame to touch the balloon. What happens? The balloon breaks, perhaps even before the flame touches it. Light another match. Hold it directly under the water in the second balloon. Allow the flame to touch the balloon. What happens to this balloon? It doesn't break. Why does the balloon with no water break in the flame? The flame heats the rubber of both balloons. The rubber of the balloon without water becomes so hot that it becomes too weak to _ the pressure of the air inside the balloon. However, when the balloon with water in it is placed in the flame, the water takes in most of the heat from the flame. Then, the rubber of the balloon doesn't become very hot, it doesn't weaken, and the balloon doesn't break. Water is a particularly good absorber of heat. It takes a lot of heat to change the temperature of water. On the other hand, when water cools, it gives off a great deal of heat. That's why areas near oceans or other large bodies of water don't get as cold in winter as areas at the same latitude further inland. Question: From the passage we can know the following aspects of the experiment except _ . Options: A: method B: material C: result D: time
A: D

*Question*
Read the article and select the best answer. Article: Native American sand paintings are a very beautiful and popular art form for collectors today. But traditionally, the paintings are created to heal a person during a ceremony. The type of image and ceremony used is determined by the disease which the person is suffering from. The sand painting may contain an image of the Holy People. The tribe medicine man may ask the Holy People to help him paint the image and therefore help heal the person in need. When the medicine man finishes painting, he checks its accuracy. The order and the symmetry of the painting symbolize the harmony which a patient wishes to achieve in his or her life. The accuracy of a sand painting is believed to determine its healing effects. In some cases, more than one sand painting might be used in a healing ceremony. During the ceremony, the person who needs healing will sit on the Native American sand painting. The sand painting serves as an entrance for the spirits and through the painting, the person can absorb the healing energies from these spirits. The sand paintings were not originally meant to be sold or hung on the wall. Once the ceremony is completed, the sand painting must be destroyed, thus allowing the sand to return to the Earth. This is necessary because the sand painting is now seen as poisonous, having absorbed the illness, and must be destroyed. The entire ceremony, from the painting to the destroying is usually completed within a 12-hour period. The medicine man never wrote down how to perform the healing ceremony, but it was passed down from generation to generation. The Pueblo tribe was the first tribe to create Native American sand paintings, but the art soon spread to many other tribes. Today, it is the Navajos who are the most active in creating Native American sand paintings. It is believed that it was a medicine man named Fred Stevens who was the first person to create a Native American sand painting for sale in the 1950s. A trader, Rex Bollin, recommended Fred to sell sand paintings since they were so beautiful.... Question: From this passage we can infer that _ . Options: A: different images would be painted to cure different diseases B: the Pueblo tribe was unwilling to show other tribes how to create sand paintings C: an ancient medicine man wrote down how to perform the healing ceremony to pass it down D: The Navajos were the creators of Native American sand paintings
**Answer**
A