Fill in the brackets with the appropriate prime number 20 = () + () 19 = () + () 35 = () × () 17 = () + () × () Fill in the brackets with the appropriate prime number 20 = () + () 19 = () + () 35 = () × () 17 = () + () × () Two exactly the same right angle trapezoid, can be put together into a (), can also be put together into a () Natural numbers greater than 0 are both primes and even numbers (); () are neither primes nor composite numbers.

Fill in the brackets with the appropriate prime number 20 = () + () 19 = () + () 35 = () × () 17 = () + () × () Fill in the brackets with the appropriate prime number 20 = () + () 19 = () + () 35 = () × () 17 = () + () × () Two exactly the same right angle trapezoid, can be put together into a (), can also be put together into a () Natural numbers greater than 0 are both primes and even numbers (); () are neither primes nor composite numbers.

20=（3）+（17） 19=（2）+（17） 35=（5）×（7） 17=（2）+（3）×（5）

Calculate and fill in the brackets with the proper prime numbers 24 = () + (), 40 = () + (), 94 = () + (), 20 = () + (), 70 = () + (), 100 = () + ()

24=17+7
40=33+7
94=89+5
20=13+7
70=67+3
100=97+3

Please write down prime numbers within 20______ ．

Prime numbers within 20 are: 2, 3, 5, 7, 11, 13, 17, 19. So the answer is: 2, 3, 5, 7, 11, 13, 17, 19