两电荷量均为+Q的点电荷放在x轴上的坐标原点O及x=L处,能正确反映出两电荷连线上场强的大小E随坐标x变化的关系图象是 [ ]
A、
B、
C、
D、
答案:B
某厂原计划3天生产690台机器,实际每天比原计划多生产35台,实际每天生产多少台?
Christmas is the anniversary of the birth of Christ, generally celebrated on December 25. It is one of the chief festivals of the Christian calendar and is (51) a social and family holiday. Christmas customs vary from (52) and among groups of different national (53) In most areas, however, homes and public places are (54) with evergreens, Christmas trees, (55) lights, and glittering ornaments. It is the busiest time of the year for merchants, and shops are filled (56) lavish displays and merchandise of all sorts. People send Christmas cards and buy gifts for their families and friends. Children look forward to (57) Santa Claus. They (58) their stockings on Christmas (59) and on Christmas morning they discover the gifts that have been left for them during the night. In the afternoon, families gather to (60) presents and to share the traditional Christmas dinner.
55().
A. coloring
B. colored
C. colors of
D. colorless