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Come with a math mind. . . Urgent! ! ! ! !
First, you have to understand what a prime number is:

A prime number is an integer that can be expressed as the product of itself and 1, and cannot be expressed as the product of any two other integers. For example, 15 = 3 * 5, then 15 is not a prime number; Another example is 12 = 6 * 2 = 4 * 3, so 12 is not a prime number. On the other hand, 13 cannot be expressed as the product of any other two integers except 13 * 1, so 13 is a prime number.

Draw a figure of length, width and height with a, b and c respectively.

According to: the sum of the areas of the front and the upper two faces is 209 square centimeters.

Therefore: ab+AC = 209a (b+c) = 20911×19 = 209.

So: a= 1 1 or 19.

Suppose a =19 b+c =11. According to the calculation, B and C do not satisfy the condition that the length, width and height are prime numbers.

Therefore, from a =11b+c =19, we can deduce that b = 2c = 17 or b= 17 c=2.

So we get a =11b = 2c =17 or a =11b =17c = 2.

Rectangular volume: v = ABC =1/kloc-0 /× 2×17 = 374 cm2.