7 The triangular faces of a right square pyramid are at an angle of $60^{\circ}$ to the base. The height of the pyramid is $30 \mathrm{~m}$. Find the perimeter of the base of the pyramid, correct to 1 decimal place.

Step 1 ：We are given a right square pyramid with a height of 30 meters and the angle between the triangular face and the base is 60 degrees.

Step 2 ：We can use trigonometry to find the length of the side of the base. The tangent of the given angle is equal to the height divided by half of the side length.

Step 3 ：Rearranging this, we get \(\text{side length} = \frac{\text{height}}{\tan(\text{angle}/2)}\).

Step 4 ：Substituting the given values, we get \(\text{side length} = \frac{30}{\tan(60/2)} = 34.641016151377556\) meters.

Step 5 ：The perimeter of the base of the pyramid is 4 times the side length, so \(\text{perimeter} = 4 \times \text{side length} = 4 \times 34.641016151377556 = 138.6\) meters.

Step 6 ：Final Answer: The perimeter of the base of the pyramid is \(\boxed{138.6}\) meters.