The complete list of subsets of the set {1, a, b, 2} is: {}, {1}, {a}, {b}, {2}, {1, a}, {1, b}, {1, 2}, {a, b}, {a, 2}, {b, 2}, {1, a, b}, {1, a, 2}, {1, b, 2}, {a, b, 2}, {1, a, b, 2}.
The subset of a set is a set that contains only elements that are also in the original set. In the case of the set {1, a, b, 2}, the subsets are:
The empty set: {}
Single-element subsets: {1}, {a}, {b}, {2}
Two-element subsets: {1, a}, {1, b}, {1, 2}, {a, b}, {a, 2}, {b, 2}
The set itself: {1, a, b, 2}
Therefore, the complete list of subsets of the set {1, a, b, 2} is:
{}, {1}, {a}, {b}, {2}, {1, a}, {1, b}, {1, 2}, {a, b}, {a, 2}, {b, 2}, {1, a, b}, {1, a, 2}, {1, b, 2}, {a, b, 2}, {1, a, b, 2}.