Answer: B. $7$

Explanation:1. Recall the formula for the area of a rectangle: The area $A$ of a rectangle is given by $A = \text{length} \times \text{width}$.

2. Identify the given values: Area $A = 630$ square inches. Length $L = 90$ inches. We need to find the width $W$.

3. Substitute the values into the formula: $630 = 90 \times W$

4. Solve for the width W: Divide both sides by $90$: $W = \dfrac{630}{90}$ $W = \dfrac{63}{9}$ $W = 7$

5. State the units: The width is in inches.

6. Conclusion: The width of the rectangle is $7$ inches.