1. $\ell=6$ in. $w=1$ in., $h=4$ in

Step 1 ：Given that the length (l) is 6 inches, the width (w) is 1 inch, and the height (h) is 4 inches.

Step 2 ：The volume of a rectangular prism is given by the formula \(\ell \times w \times h\).

Step 3 ：Substituting the given values into the formula, we get \(6 \times 1 \times 4\).

Step 4 ：Calculating the above expression, we find that the volume of the rectangular prism is \(\boxed{24}\) cubic inches.