两个电阻串联后的总电阻是10Ω，并联后的总电阻是2.4Ω，则这两_爱下问搜题

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问题填空题

两个电阻串联后的总电阻是10Ω，并联后的总电阻是2.4Ω，则这两个电阻的阻值分别是和。

答案

6Ω，4Ω

完形填空

Ever since 1 was little, my favorite season was winter. I loved to play in the snow and enjoyed the hot chocolate.
1 , winter never gave me the special gift of snow on my birthday. I would ask my grandmother 2 it didn’t snow on my birthday. She would laugh and tell me I asked too many questions.   3 one day, she promised that she would make it snow on my next birthday.
That year,   4 my birthday, my grandmother died. I was sad but angry because she had promised to make it snow. The day of my sixth birthday, I woke up and ran to the window, hoping to see just one snowflake(雪花). But there was no   5  . I felt mad at my grandmother. She had broken a promise.
By my sixteenth birthday, I   6 all hope of getting my snow, even though I still wished for it.
During my party, I stayed with my friends and family and was truly    7 . I 8 the best time ever! Then I saw the white snow   9 down all around. I was so excited that I ran around screaming and laughing. My friends all laughed   10 me, but I didn’t care.
When I   11 home, my grandpa said he had a gift for me. I was   12 because he had given me a gift. It was a small white box, which looked old. I opened it. There was a crystal snowflake(冰晶雪花)with a card that    13 , “Happy Birthday.”
How could this be? My grandpa said it was my grandmother’s final   14 on my “sweet sixteenth”. I cried.
I was   15 that my smiling grandmother angel was and had been watching over me.

C．Importantly

C．disappearing

问答题

一辆值勤的警车停在公路边，当警员发现从他旁边以v₀=10m/s的速度行驶的货车严重超载时，决定前去追赶，经过t₀=5s后警车发动起来，并以a=2m/s²的加速度做匀加速运动，但警车的行驶速度必须控制在v_m=72km/h以内，问：

（1）警车发动后，经多少时间警车与货车达共同速度？

（2）警车发动后，经多少时间达到其最大速度？

（3）警车发动后要多长时间才能追上货车？