1's complement of 100100 is a. 0101100 b. 0110110 c. 0100110 d. 0100111 e. None of these

To find the 1's complement of a binary number, we need to invert each bit of the number. In other words, we need to change all 0s to 1s and all 1s to 0s.<br /><br />Given the binary number 100100, let's invert each bit:<br /><br />- The first bit is 1, so we change it to 0.<br />- The second bit is 0, so we change it to 1.<br />- The third bit is 0, so we change it to 1.<br />- The fourth bit is 1, so we change it to 0.<br />- The fifth bit is 0, so we change it to 1.<br />- The sixth bit is 0, so we change it to 1.<br /><br />Therefore, the 1's complement of 100100 is 0110110.<br /><br />So, the correct answer is option b. 0110110.