A(n) is one that appears to be an agreement but lacks an essential requirement for validity and enforceability.

A void contract

Explanation:

A void contract is one that appears to be an agreement but lacks an essential requirement for validity and enforceability. A void contract is usually illegitimate contract which cannot be enforceable. For example, an agreement between a drug trafficker and his clients is a void contract because it is illegal.

answer; shays rebellion;

answer; they burn down the bushes and trees;