Final answer:
Congress can make laws on issues that are not mentioned in the Constitution because of the implied powers and the necessary and proper clause.
Step-by-step explanation:
Congress can make laws on issues that are not mentioned in the Constitution because of the implied powers and the necessary and proper clause. Implied powers are powers that are not explicitly stated but are inferred as necessary to achieve the objectives of the national government. The necessary and proper clause, also known as the elastic clause, grants Congress the authority to make laws that are necessary and proper for carrying out its enumerated powers.