Final answer:
To calculate the binary expansion of 28 in descending order, you need to divide 28 by 2 repeatedly and note down the remainders in reverse order. The binary expansion of 28 in descending order is 11100.
Step-by-step explanation:
To calculate the binary expansion of 28 in descending order, we divide 28 by 2 repeatedly until the quotient becomes 0. The remainders in the division process form the binary digits in descending order. Starting with 28, we get a remainder of 0. Dividing the quotient 14 by 2, we get a remainder of 0 again. Continuing this process, we get remainders of 1, 1, and 0 when dividing the quotients 7, 3, and 1 by 2, respectively. Finally, the binary expansion of 28 in descending order is 11100.