Amira leans a 16 -foot ladder against a wall so that it forms an angle of $66^{\circ}$ with the ground. What's the horizontal distance between the base of the ladder and the wall? Round your answer to the nearest hundredth of a foot if necessary.

Step 1 ：Given the length of the ladder (16 feet) and the angle it forms with the ground (66 degrees), we need to find the horizontal distance between the base of the ladder and the wall.

Step 2 ：Since this is a right triangle problem, we can use trigonometry to solve it. Specifically, we can use the cosine function to find the horizontal distance (adjacent side) given the hypotenuse (ladder length) and the angle: \[\cos(\text{angle}) = \frac{\text{adjacent}}{\text{hypotenuse}}\]

Step 3 ：Rearrange the formula to solve for the adjacent side (horizontal distance): \[\text{adjacent} = \text{hypotenuse} \times \cos(\text{angle})\]

Step 4 ：Plug in the given values: hypotenuse = 16 feet and angle = 66 degrees. Calculate the horizontal distance: \[\text{adjacent} = 16 \times \cos(66^\circ)\]

Step 5 ：Calculate the cosine of 66 degrees and multiply by 16: \[\text{adjacent} \approx 6.51\]

Step 6 ：\(\boxed{\text{The horizontal distance between the base of the ladder and the wall is approximately 6.51 feet.}}\)