set a contains 6 letters and 6 numbers. set b contains 2 letters and 6 numbers. 2 letters and 5 numbers are common to both sets a and b. find the number of elements in set a or set b.

s separated by blocks of $2
s with $n$ $2
s in the $n^{\rm{th}}$ block. What
The combining power of an element is called ? A. coefficient B.subscript C.periodicity D.valence number
pls pls ha44aalp x =x=x, equals ^\circ ∘