1.一个五位数的前三个数字所组成的三位数以及后两个数字所组成的两位数,分别是两个自然数的平方,这两个自然数的和与差的比是5:2,两个自然数的最大公约数是3。你知道这个五位数是多少？2.9以内的素数只有2、3、5、7四个。红旗小学学生的人数,是一个由三个素数数码所组成的三位数,这个三位数又是 1. The three digits of the first three digits of a five-digit number and the two digits of the last two digits are the squares of two natural numbers, the sum of which is 5: 2, The greatest common divisor of two natural numbers is three. Do you know what the five-digit number is? The prime numbers within 2.9 are only 2, 3, 5, and 4 four. The number of primary school students in Hongqi is a three-digit number composed of three prime numbers, which in turn is