The cardinal number of set A is 9
The set is given as:
A = {x|x is a letter in the word introduce}
This means that the set A is:
A = {i,n,t,r,o,d,u,c,e}
The cardinal number of set A is represented as:n(A)
i.e. the number of elements in the set.
When the characters are counted, we have:
n(A) = 9
Hence, the cardinal number of set A is 9
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