.
⑵ （2010•石景山區二模）下列元素中，屬於金屬元素的是（） A．氧 B．氟 C．硅 D．銅
A、氧不帶抄「釒」字旁襲，屬於非金屬元素，故A錯；
B、氟不帶「釒」字旁，屬於非金屬元素，故B錯；
C、硅不帶「釒」字旁，屬於非金屬元素，故C錯；
D、銅帶「釒」字旁，屬於金屬元素，故D正確．
故選D．
⑶ （2012石景山區二模）建築工地上常用如圖所示的裝置搬運建築材料，使用的滑輪組由a、b、c、d、e五個滑輪
如圖，n=4，
∵不計繩重及摩擦，
∴F=
（G+G
動）=
（1500N+50N×2）=400N，
拉力端移動的速度：
v=4×0.5m/s=2m/s，
拉力做功功率：
P=Fv=400N×2m/s=800W．
故答案為：800．
⑷ （2014石景山區二模）小華在探究光的反射規律的實驗中，進行了如圖所示的實驗，先將紙板B以ON為軸轉動到
（1）改變紙板B的位置，使其與紙板A不在同一平面上，看看紙板B上是否有反射內光線，即可得到結論．容
（2）由讓光線逆著OF的方向射向鏡面，會發現反射光線沿著OE方向射出可知，將反射光線改為入射光線，光路圖照樣成立，體現了光路是可逆的．
故答案為：（1）將紙板B向後轉動；（2）反射現象中，光路可逆．
⑸ （2014石景山區二模）如圖，已知△ABC中，∠B=50°，若沿圖中虛線剪去∠B，則∠1+∠2等於（）A．130
∠BDE+∠BED=180°-∠B，
=180°-50°，
=130°，
∠1+∠2=360°-（∠BDE+∠BED），
=360°-130°，
=230°．
故選：B．
⑹ （2011石景山區二模）兩個實心正方體A、B由密度均為ρ的同種材料製成，它們的重力分別是GA、GB，且B物體
∵正方體邊長LB=2LA，
∴VA：VB=（LA）3：（LB）3=1：8，
底面積之比：
SA：SB=（LA）2：（LB）2=1：4，
∵專G=mg=ρVg，AB密度相同，
∴GA：GB=ρVAg：ρ屬VBg=VA：VB=1：8，故B錯；
∵p=
=
，
∴p
A：p
B=
：
=
：
=1：2，故D錯；
η
甲=
=
，
η
乙=
=
=
，
∵η
甲：η
乙=41：48，
即
：
=41：48，
化簡得：
G
A：G
動=5：1，
∴G
B：G
動=40：1，故C錯；
當A在水中勻速上升時，
η=
=
=
=
=
=80%，
解得：ρ
A=5×10
3kg/m
3，故A正確．
故選A．
⑺ 石景山區16年六年級英語畢業考試
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?