The problem involves understanding how to rewrite and evaluate expressions based on the Associative Property of Multiplication, which states that the grouping of numbers does not affect the product.

Let's answer the questions step by step:

1. The expression was rewritten using the Associative Property of Multiplication. This property allows us to change the grouping of factors in a multiplication expression without changing the result.

2. Now, let's calculate the expression from Line 1:

   $(5 \cdot 2) \cdot 4 = 10 \cdot 4 = 40$

   So, $(5 \cdot 2) \cdot 4 = 40$.

3. Next, calculate the expression from Line 2:

   $5 \cdot (2 \cdot 4) = 5 \cdot 8 = 40$

   So, $5 \cdot (2 \cdot 4) = 40$.

Thus, both expressions are equivalent, and the final answer is 40.

Here's the filled-in solution:

The expression was rewritten using the Associative Property of Multiplication.
$(5 \cdot 2) \cdot 4 = 10 \cdot 4 = 40$ $5 \cdot (2 \cdot 4) = 5 \cdot 8 = 40$

Would you like further details or have any questions?

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Here are 5 related questions:

1. How does the Associative Property differ from the Commutative Property?
2. Can you explain the Distributive Property with an example?
3. What happens if you apply the Associative Property to division instead of multiplication?
4. How can you use the Associative Property to simplify complex calculations?
5. Are there any other operations besides multiplication where the Associative Property applies?

Tip:

When solving expressions, always remember that the order of operations (PEMDAS) guides the sequence: Parentheses first, then Exponents, followed by Multiplication/Division, and finally Addition/Subtraction.