What quantity (in mL) of a 45% acid solution?

The provided question and solution are incomplete and lack context. To solve for the quantity of a 45% acid solution, we need additional information, such as the desired amount of pure acid or the total volume of a diluted solution. A complete problem would provide information such as: 'What quantity (in mL) of a 45% acid solution is needed to obtain 150 mL of pure acid?' or 'What quantity (in mL) of a 45% acid solution needs to be added to 200 mL of water to create a solution of a specific concentration?' Without this additional context, a complete and accurate solution cannot be provided.