1. The problem asks to solve the binary addition $10_2 + 11_2$ and find the correct binary sum. 2. Binary addition works similarly to decimal addition but carries over when the sum reaches 2 (since binary is base 2). 3. Add the digits from right to left: - $0 + 1 = 1$ - $1 + 1 = 10_2$ (which is 0 with a carry of 1) - Carry the 1 to the next left digit: $1 + 0 + 1 = 10_2$ (0 with another carry of 1) - Since there are no more digits, the carry 1 becomes the leftmost digit. 4. So the sum is: $$10_2 + 11_2 = 101_2$$ 5. The correct answer for question 3 is A) $101_2$. 6. Now, question 4 asks to subtract $10_2$ from $1011_2$. 7. Convert both to decimal to understand subtraction: - $1011_2 = 1\times2^3 + 0\times2^2 + 1\times2^1 + 1\times2^0 = 8 + 0 + 2 + 1 = 11$ - $10_2 = 2$ 8. Subtract in decimal: $11 - 2 = 9$ 9. Convert 9 back to binary: - $9 = 8 + 1 = 2^3 + 2^0 = 1001_2$ 10. So, $1011_2 - 10_2 = 1001_2$. 11. The correct answer for question 4 is A) $1001_2$.