The full adder adds the Kth bits of two numbers to theSum of previous bitSum of all previous bitsDifference of the previous bits          carry from (K-1)th bit

The full adder adds the Kth bits of two numbers to the carry from the (K-1)th bit. Here's a step-by-step explanation:

1. The full adder is a digital circuit that performs the addition of numbers. In this case, we're looking at the addition of the Kth bits of two numbers.

2. The full adder also takes into account if there was a carry from the addition of the (K-1)th bits. A carry occurs when the sum of the bits in a binary addition is 2 (binary 10) or more.

3. The full adder then adds these three values: the Kth bit of the first number, the Kth bit of the second number, and the carry from the (K-1)th bit.

4. The result is a sum for the Kth bit and a carry that will be used in the addition of the (K+1)th bits.

5. This process is repeated for all bits in the numbers being added, from the least significant bit (K=0) to the most significant bit.

So, the full adder doesn't add the sum or difference of all previous bits, it only adds the Kth bits of the two numbers and the carry from the (K-1)th bit.