The following equation has been simplified incorrectly. \[ \begin{aligned}-3^{2} \cdot 5-(18 \div 2) \cdot 4 & =9 \cdot 5-(18 \div 2) \cdot 4 \\ & =9 \cdot 5-(9) \cdot 4 \\ & =45-(9) \cdot 4 \\ & =36 \cdot 4 \\ & =144\end{aligned} \] Step 1 of 2 : Determine which step(s) of the calculation do not follow the correct order of operations. \( \begin{array}{l}\square-3 \cdot 5-(18 \div 2) \cdot 4=9 \cdot 5-(18 \div 2) \cdot 4 \\ \text { Answer } \\ \square 9 \cdot 5-(18 \div 2) \cdot 4=9 \cdot 5-(9) \cdot 4 \\ \square 9 \cdot 5-(9) \cdot 4=45-(9) \cdot 4 \\ \square 45-(9) \cdot 4=36 \cdot 4\end{array} \quad \begin{array}{l}\square 36 \cdot 4=144\end{array} \)

In this equation, the third step contains a miscalculation where the subtraction has not been performed correctly. After calculating \(9 \cdot 5\) as 45 and \(9 \cdot 4\) as 36, the proper operation would be to subtract those two results, not multiply them. So it should be \(45 - 36\), leading to a final result of 9, not the incorrect multiplication stated. Another mistake occurs in the first simplification step where \(-3^{2}\) should actually be evaluated as \(- (3^2)\), resulting in \(-9\). Therefore, the starting point should be \(-9 \cdot 5 - (9) \cdot 4\) which fundamentally changes the entire calculation thereafter. Always remember to carefully handle signs and follow the order of operations!