Directions: Complet the following passage by filling in each blank with one word that best

Directions: Complet the following passage by filling in each blank with one word that best fits the context.
When very small dinosaur bones were found in a Germany mine people thought they were from baby dinosaurs. 48 , scientist Martin Sander's work shows that they were probably fully grown and belong to the smallest giant dinosaur species ever found.
Growth marks on dinosaur bones are similar 49 growth rings on trees. The rings are far apart while the animal is young and growing quickly. 50 get closer as growth slows. It is exactly these tight ring marks that we found in the fossil (化石) bones, says Sander. So the fossils must have been from adult animals.
51 was this German dinosaur so much smaller than other giant dinosaurs, which grew up to 45 metres long and weighed as much as a thousand humans?
150 million years ago, most of Germany was underwater. Scientists think that 52 water levels rose, there was less and less land and food available. The dinosaur was forced to adapt and evolved into 53 smaller animal needing 54 space and food.
Since 1998, scientists have dug up more than 1,000 dinosaur fossils in the mine. It is one of the few places in the world 55 the bones and footprints of dinosaurs have been found together.48. However 49. to 50. They 51. Why

(答案→)48. However 49. to 50. They 51. Why 解析：可联系答.案.网客服索取。

我学会了

我学会了

C解析分析：教材中介绍了伽利略对落体规律的研究以及“理想斜面实验”，通过这些知识的学习，可以明确伽利略所创造的这一套科学研究方法．解答：这是依据思维程序排序的问题，这一套科学研究方法，要符合逻辑顺序，即通过观察现象，提出假设，根据假设进行逻辑推理，然后对自己的逻辑推理进行实验检验，紧接着要对实验结论进行修正推广．
故选C．点评：伽利略将可靠的事实和理论思维结合起来，以实验事实为基础，开辟了崭新的研究物理的方法道路，同学们要从中汲取营养，提高科学素质．