Final answer:
The necessary or proper clause, also known as the 'elastic clause,' is included in Covenant number 18. This clause grants Congress implied powers beyond those specifically listed in the Constitution. It has been used historically to justify the expansion of Congressional powers.
Step-by-step explanation:
The clause that is also seen in the promissory note and is included in Covenant number 18 is the necessary or proper clause, also known as the “elastic clause.” This clause is found in Section 8, Clause 18 of the United States Constitution and is the basis for Congress' implied powers. It allows Congress to take actions beyond those specifically listed in the Constitution as long as they are deemed necessary and proper to execute its delegated powers. This clause has been historically used to justify the expansion of Congressional powers and the creation of various federal government programs.