(And in general, prove that if we assign the same number to an arbitrary number

(And in general, prove that if we assign the same number to an arbitrary number that has an odd number of digits, we get a number divisible by 11.) b) If you add to an arbitrary number a number written with the same digits in reverse order, then the resulting number will be divided by 11 without a remainder: for example, numbers of the form aa, abba, abccba are multiples of