To solve the problem of finding the cardinality of a set \( A \) and its power set \( P(A) \), we need to understand the following:
The cardinality of a set \( A \), denoted as \(|A|\), is the number of elements in the set.
The power set \( P(A) \) of a set \( A \) is the set of all subsets of \( A \), including the empty set and \( A \) itself.
The cardinality of the power set \(|P(A)|\) is \(2^{|A|}\).
Given the set \( A = \{9, 8, 0, 2, 7\} \), we can calculate \(|A|\) and \(|P(A)|\).
Solution Approach
Determine the number of elements in set \( A \).
Calculate the power set's cardinality using the formula \(2^{|A|}\).
Step 1: Determine the Cardinality of Set \( A \)
The set \( A \) is defined as \( A = \{0, 2, 7, 8, 9\} \). The cardinality of set \( A \), denoted as \( |A| \), is the number of elements in the set. Thus, we have:
\[
|A| = 5
\]
Step 2: Calculate the Cardinality of the Power Set \( P(A) \)
The power set \( P(A) \) is the set of all subsets of \( A \). The cardinality of the power set is given by the formula:
\[
|P(A)| = 2^{|A|}
\]
Substituting the value of \( |A| \):
\[
|P(A)| = 2^5 = 32
\]
Final Answer
The cardinality of set \( A \) is \( \boxed{|A| = 5} \) and the cardinality of the power set \( P(A) \) is \( \boxed{|P(A)| = 32} \).