The unit digit in the product (281 × 15 × 16 × 18) is :

Unit digit of 1³+2³+3³+...+9³ is

The value of a 2-digit number is 5 times the sum of the digits. What is the product of the digits ?

What is the digit at the 100th place of number (225)⁴⁰ ?

What is the last digit of the sum S = 9²⁷ + 27⁹ ?

The product of the digits of a two-digit number is 36. If 45 is subtracted from the number, then the digits interchange mutually. The number is