A. To convert 101.11two to base 10, we can use the place value system. Each digit in the binary number represents a power of 2. So, 101.11two is calculated as follows:
(1 * 2^2) + (0 * 2^1) + (1 * 2^0) + (1 * 2^-1) + (1 * 2^-2) = 4 + 0 + 1 + 0.5 + 0.25 = 5.75
Therefore, 101.11two is equal to 5.75 in base 10.
B. To convert 0.11two to base 10, we have:
(0 * 2^0) + (1 * 2^-1) + (1 * 2^-2) = 0 + 0.5 + 0.25 = 0.75
Therefore, 0.11two is equal to 0.75 in base 10.
C. To convert 111.111two to base 10, we have:
(1 * 2^2) + (1 * 2^1) + (1 * 2^0) + (1 * 2^-1) + (1 * 2^-2) + (1 * 2^-3) = 4 + 2 + 1 + 0.5 + 0.25 + 0.125 = 7.875
Therefore, 111.111two is equal to 7.875 in base 10.