图甲为某一小灯泡的U-I图线，现将两个这样的小灯泡并联后再与一个4Ω的定值电阻R串联，接在内阻为1Ω、电动势为5V的电源两端，如图乙所示，则（ ）
A．通过每盏小灯泡的电流强度为0.2A，此时每盏小灯泡的电功率为0.6W
B．通过每盏小灯泡的电流强度为0.3A，此时每盏小灯泡的电功率为0.6W
C．通过每盏小灯泡的电流强度为0.2A，此时每盏小灯泡的电功率为0.26W
D．通过每盏小灯泡的电流强度为0.3A，此时每盏小灯泡的电功率为0.4W
设通过每个小灯泡的电流为I，电压为U，则电路中总电流为2I．根据闭合电路欧姆定律得
U=E-2I（R+r）
代入得：U=5-10I
当U=0时，I=0.5A；当I=0时，U=5V，
在U-I图上作出U=5-10I的图象如图，此图线与小灯泡的U-I图线的交点即为乙图状态下小灯泡的工作状态，
由图读出通过每盏小灯泡的电流强度为I=0.3A，电压为U=2V，则此时每盏小灯泡的电功率为P=UI=0.6W．
故选B
“Jane, please let me borrow a dollar,” Jenny asked as they stood in the school lunch line. “I have one in my jacket, but I don’t want to 1 and lose my place.” “OK,” agreed Jane. Jane waited all day for Jenny to 2 back the dollar she borrowed, but Jenny always seemed to be 3 . “She’s just forgotten,” thought Jane. “I don’t want to make her angry.” Still, her money didn’t go 4 . Some classmates, like Jenny, were 5 five dollars a week. Weeks went by. At last Jane got up enough courage (勇气) to tell her about the money. “Oh Jane, I 6 !” Jenny said. “I’ll bring the dollar tomorrow.” The next day Jenny seemed to have forgotten again. During the noon hour Jane saw her buying sweets for Mary and Ann. Jenny saw Jane looking at her. 7 she said something in a low voice to the other two girls. Jane felt 8 and asked her teacher if she could go back to the classroom. In the classroom, Jane saw two new pencils in Jenny’s desk. An 9 came to her. “Jenny’s not 10 lately, and anyway, she really owes (欠) me. Besides, she has all money to buy more. A dollar doesn’t mean anything to her, but it means a lot to me.”
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每个COCl2分子内含有 个δ键， 个π键。其中心原子采取 杂化轨道方式。