某生药粉末的氯仿浸液滴于载玻片上，挥干溶剂，滴加10%盐酸苯肼试液，显微镜下可见桂皮

下列各式中能用完全平方公式分解的是（　　）

A．x²-8x+9

B．a²+14a+49

C．4x²-20x-25

D．-2ab+a²-b²

IV.短文改错(10)

Did you enjoy yourself yesterday? I suppose you do. But I’d like to tell you what a bad day I had yesterday. Everything just went wrongly. On the morning, my alarm clock didn’t ring, since I woke up an hour late. I was in such a hurry that I burnt my hand when I was cooking the breakfast. Then I ran out of the house to catch the 8:30 buses. This is the bus I usually take. But, you may laugh, I missed it of course. I am very unhappy, and scared as well because teacher hates the students coming late to school. So I ran three miles to school only to found that nobody was there. The school was quiet but peaceful. Our classroom was locked. I realized that moment: It was Sunday.

碳酸盐岩中的颗粒大体有（）2类。

A、生物碎屑颗粒和非生物碎屑颗粒

B、内颗粒和外颗粒

C、鲕粒和藻粒

D、球粒和藻粒

效应（effect）

在胰液中凝乳作用较强的酶是

A．胰脂肪酶
B．胰淀粉酶
C．胰蛋白酶
D．糜蛋白酶
E．羧基肽酶