Which member of the plural executive is responsible for verifying that the state of texas has adequate revenue to pay for a piece of legislation?

The comptroller

Explanation:

The Legislative of Texas elects six out of seven people who constitutes the "plural executive". The Plural Executive consists of

1. the Governor

2.the Lieutenant Governor

3.  the Attorney General

4. the Land Commissioner

5. the Commissioner of Agriculture

6. the Comptroller

7. the Commissioner of the General Land Office.

The Comptroller  is State executive who is responsible for the collection of taxes and other revenues. He is also in charge of estimating the future revenue. It is the Comptroller who verifies whether the State of Texas has adequate revenue to pay for a piece of legislature.

Thus the answer is the "comptroller" of the plural executive.

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