Murphy & Johnson is a privately owned manufacturer of small motors for lawnmowers, tractors, and snowmobiles. The components of its financial statements are (1) income before taxes = $21 million, (2) total assets = $550 million, and (3) total revenues = $775 million. Murphy & Johnson's CPA firm uses the normal percentage for income before taxes for a public company for determining overall materiality.

a. Determine overall materiality, and determine tolerable misstatement. Justify your decisions.

b. During the course of the audit, Murphy & Johnsons CPA firm detected two misstatements that aggregated to an overstatement of income of $1.25 million. Evaluate the audit findings. Justify your decisions.