.
⑵ （2010•石景山区二模）下列元素中，属于金属元素的是（） A．氧 B．氟 C．硅 D．铜
A、氧不带抄“钅”字旁袭，属于非金属元素，故A错；
B、氟不带“钅”字旁，属于非金属元素，故B错；
C、硅不带“钅”字旁，属于非金属元素，故C错；
D、铜带“钅”字旁，属于金属元素，故D正确．
故选D．
⑶ （2012石景山区二模）建筑工地上常用如图所示的装置搬运建筑材料，使用的滑轮组由a、b、c、d、e五个滑轮
如图，n=4，
∵不计绳重及摩擦，
∴F=
（G+G
动）=
（1500N+50N×2）=400N，
拉力端移动的速度：
v=4×0.5m/s=2m/s，
拉力做功功率：
P=Fv=400N×2m/s=800W．
故答案为：800．
⑷ （2014石景山区二模）小华在探究光的反射规律的实验中，进行了如图所示的实验，先将纸板B以ON为轴转动到
（1）改变纸板B的位置，使其与纸板A不在同一平面上，看看纸板B上是否有反射内光线，即可得到结论．容
（2）由让光线逆着OF的方向射向镜面，会发现反射光线沿着OE方向射出可知，将反射光线改为入射光线，光路图照样成立，体现了光路是可逆的．
故答案为：（1）将纸板B向后转动；（2）反射现象中，光路可逆．
⑸ （2014石景山区二模）如图，已知△ABC中，∠B=50°，若沿图中虚线剪去∠B，则∠1+∠2等于（）A．130
∠BDE+∠BED=180°-∠B，
=180°-50°，
=130°，
∠1+∠2=360°-（∠BDE+∠BED），
=360°-130°，
=230°．
故选：B．
⑹ （2011石景山区二模）两个实心正方体A、B由密度均为ρ的同种材料制成，它们的重力分别是GA、GB，且B物体
∵正方体边长LB=2LA，
∴VA：VB=（LA）3：（LB）3=1：8，
底面积之比：
SA：SB=（LA）2：（LB）2=1：4，
∵专G=mg=ρVg，AB密度相同，
∴GA：GB=ρVAg：ρ属VBg=VA：VB=1：8，故B错；
∵p=
=
，
∴p
A：p
B=
：
=
：
=1：2，故D错；
η
甲=
=
，
η
乙=
=
=
，
∵η
甲：η
乙=41：48，
即
：
=41：48，
化简得：
G
A：G
动=5：1，
∴G
B：G
动=40：1，故C错；
当A在水中匀速上升时，
η=
=
=
=
=
=80%，
解得：ρ
A=5×10
3kg/m
3，故A正确．
故选A．
⑺ 石景山区16年六年级英语毕业考试
一、1.This is my head. ( B ) 2. What are you doing? ( A ) 3. There is a cat on the bed. ( B ) 4. In spring, the leaves are green. ( A ) 5. Thank you very much. ( C ) 6. I usually wash clothes on the weekend. ( A ) 7.I usually write an e-mail to my grandma on Sunday . ( B ) 8. My birthday is Oct.12th. ( C ) 9. Where are Amy and ChenJie ? They are running to us . ( C ) 10. Look, her come two tigers . ( B ) 二、1. Today is April 3rd. ( × ) 2. I like spring best . ( √ ) 3. My mother is writing an e-mail to my uncle. (√ ) 4. I usually eat dinner at 7:30 in the evening . ( × ) 5. Amy is catching buterflies . (× ) 6. What do you do in the evening? I often read books. ( × ) 7. What is Zoom doing ? He’s counting insects . ( √ ) 8. Look , the mother panda is sleeping . ( × ) 9. Can tigers climb trees ? No, they can’t . ( × ) 10. What’s the date today? It’s March 12th. ( √ ) 三．. Are you from China? ( B ) 2. What’s the weather like in spring? ( C ) 3. What’s your aunt doing ? ( A ) 4. Happy birthday. ( C ) 5. What is the bird doing ? ( B ) 8 四．1. I usually get up at 7:15. 2. What’s your favourite season? I like fall best. 3. Why do you like fall? Because it’s always cool. 4. When is your birthday? It’s in May. 5. Sarah is watching insects . 五．A: Hello, Amy. What’s the weather like today? B: It’s cold . A: What is the date today? B: It’s December 2nd. It’s my birthday. A: Oh, really? What do you usually do on your birthday? B: I usually get up early . Then I take candy to my class. In the evening, we have a big dinner and eat a birthday cake. A: Happy birthday to you. B: Thanks. (× , √ , × , √ , × ) 六、G D B F C 七、( A.) √×√√× (B) 1.B 2. A 3. B 4. A 5. B 八、hot , swim , rains , plant , apples , Winter , cold, Sometimes , ski , snowman 九、1.What do you do on the weekend? 2. Are you listening to music? 3. What are the bears doing ? 4. What’s the weather like today ? 5. What is the date today?