Question $1$

Consider two $4$ bit binary numbers $x=0101$ and $y=1100.$

Let $c=xo+y$

Suppose $x$ is changed to $x^{\text{'}}=0001$

and then, $c^{\text{'}}=x^{\text{'}}o+y$

Then, $c$ and $c^{\text{'}}$ differ in which position $($from left$)$

first

fourth

third

second

Question $2$

If you xor two $4$ bit binary $x$ and $x($i$.$e$.,$ they are same$),$ the answer is

$1111$

$0000$

$00$

$11$

Question $3$

How many possible bit strings are there of $4$ bits? $($An example of a bitstring of size $4$ is $1010).$

Hint: This question is same as asking how many different outcomes are possible when you toss $4$

coins.

$2$

$32$

$8$

$16$