Show the output word produced when the following binary words

are AND$-$ed with each other and when they are OR$-$ed with each

other:

a$.1010$ and $0111$

b$.1011$ and $1100$

c$.11010111$ and $111000$

d$.$ AND$-$ing an $8-$bit binary number with $11110000$ is sometimes

referred to as $$masking$$ the lower $4$ bits. Why?