Solution:

None

The sum of numbers from 0-9(0,1,2,3,4,5,6,7,8,9) is 45 and therefore can be divisible by 3 and 9.

Solution:

All numbers(0-9) appears in alphabetical order and once.

Solution:

Turn the grid upside down. Circle the numbers 1, 9, 1, 1 When you flip it upside down the 6 becomes 9

Solution:

Forty

Solution:

7 (SEVEN-S=EVEN)

Solution:

303 , 303 , 303 , 303 , 303

Solution:

only 6

Solution:

SIX - 9 (IX) = S
9 (IX) - 10 (X) = I
40 (XL) - 50 (L) = X

=> SIX

Solution:

110 kms

72927+110 = 73037 , a palindrome