计算:sin30°+cos245°-tan45°。
解:原式=-1
=0。
化学与健康密切相关,下列相关叙述中不正确的是( )
A.人体体液的pH必须维持在一定范围内,血浆的pH正常范围是7.35~7.45
B.糖类、脂肪、蛋白质是生命活动所需能量的主要来源
C.如果某人患甲状腺肿大,应该建议马上服用补碘的药物
D.有害物质会通过多种途径进入人体,所以保护环境就是保护我们自己
用所给词的适当形式填空(必要时可加助动词)
1. __________(that) girls are Amy's sisters.
2. That is __________(she) father.
3. What's __________(you) last name?
4. These __________(picture) a while and black.
5. Here __________(be) Mona's keys.
6. __________(do) she have a dictionary?
8. Ed.Smith__________(have) 7 basketballs and 8 tennis rackets.
9. I us __________(join) the school sport club.
10. __________(Linda) father and mother are in the school.
11. __________(be) she your grandmother?