已知图G有11条边,由1个4度顶点,4个3度顶点,其余顶点的度数均小于等于2,则G中至少有( )个顶点。
A.7
B.8
C.9
D.10
参考答案:B
. ---Learning a language isn’t easy. It takes time.
---I agree. ________. There is no short cut.
A.All roads lead to Rome
B.Rome was not built in a day
C.Practice makes perfect
D.Slow but sure wins the race
所有金属都可以用氧气—乙炔气进行切割。