肺动脉瓣狭窄可出现（）
A．瘀点
B．充血性皮疹
C．瘀斑
D．血肿
E．小红痣
参考答案：B
（1）求方程6xy+4x-9y-7=0的整数解；
（2）设x、y为正整数，且x2+y2+4y-96=0，求xy的值．
Jenny _____ in the chicken when you called her at 5 o'clock this afternoon? [ ]
A. is cooking
B. was cooking
C. cooks
D. cooked
