一、填空题(本题共10小题.每小题4分,共40分) l、一个正数的算术平方根是4,则这个数是 . 2、函数y=羔的自变量x的取值 Z一￡范围是 . 3、地球上陆地的面积约149 000 000千米‘,用科学计数法表示为 千米“. 4、分解因式x。叫’一卅l= . 5、l公顷生长茂盛的树林每天大约可以吸收 First, fill in the blank questions (this question a total of 10 small questions. Each question 4 points, a total of 40 points) l, a positive arithmetic square root is 4, then this number is. 2, the function y = lamb’s value of the independent variable x The range of Z is £. 3. The area of ​​land on the earth is approximately 149 000 000 km, and it is expressed in scientific notation as kilometers. 4. The decomposition factor x is called. Lush woods can absorb approximately every day