一、填空题（每空3分，共33分）：1．如果一个数的平方等于a，那么这个数就叫做a的________；正数a有两个平方根，其中正数a的正的平方根，叫做________．2．的算术平方根是________；的平方根是________3．若1．53则________4．一般地，正数的偶次方根有两个，它们互为_______ First, fill in the blanks (3 points per empty, a total of 33 points): 1. If the square of a number is equal to a, then this number is called ________ of a; the positive number a has two square roots, and the positive square root of the positive number a is called ________. 2. The square root of the arithmetic is ________; the square root is ________3. If 1.53 then ________4. In general, there are two even roots of positive numbers, which are _______ each other