In a certain flower shop, which stocks four types of flower there are as many violets as carnation，and as many tulips as violets．If there are equal numbers of roses and tulips，what percent of the flowers in the shop are carnations ？（）

单项选择题The participants in a race consisted of 3 teams with 3 runners on each team. A team was awarded 6-n points if one of its runners finished in nth place, where 1≤n≤5. If all of the runners finshed the race and if there were no ties, was each team awarded at least one point ？（） (1)No team was awarded more than a total of 6 points. (2)No pair of teammates finished in consecutive places among the top five places.

A.条件（1）充分，但条件（2）不充分.
B.条件（2）充分，但条件（1）不充分.
C.条件（1）和（2）单独都不充分，但条件（1）和条件（2）联合起来充分.
D.条件（1）充分，条件（2）也充分.
E.条件（1）和条件（2）单独都不充分，条件（1）和条件（2）联合起来也不充分.

单项选择题A, B, and C each drove 100-mile legs of a 300-mile course at speeds of 40, 50, and 60 miles per hour, respectively. What fraction of the total time did A drive ？（）

A.A
B.B
C.C
D.D
E.E