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. 3one 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 10me, 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.

已知方程x²+y²﹣2x﹣4y+m=0．

若此方程表示圆，求m的取值范围；