What is the surface energy of a soap bubble of radus r and surface tension T?

Explanation

To find the surface energy of a soap bubble of radius \( r \) and surface tension \( T \), we can follow these steps:

### Step 1: Understand the Structure of a Soap Bubble
A soap bubble has two surfaces: the outer surface and the inner surface. This means that the total surface area of the soap bubble is twice that of a sphere.

### Step 2: Calculate the Surface Area of the Soap Bubble
The surface area \( A \) of a sphere with radius \( r \) is given by the formula:
\[
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