1_ _ _ _ _ _ _ --> 7 blanks can be filled in $2^7$
_ _ _ _ _ _ 0 0 --> 6 blanks can be filled in $2^6$
1_ _ _ _ _0 0 --> 5 blanks can be filled in $2^5$
n(AUB)=n(A)+n(B)-n(A n B)
= $2^7$ + $2^6$ - $2^5$
= $2^5$( $2^2$+ $2^1$-1)
= 32* (4+2-1)
= 32*5 ==> 160