Surface Tension Questions

If two soap bubbles of different radii are connected by a tube:

A capillary tube (A) is dipped in water. Another identical tube (B) is dipped in soap water solution. Which of the following shows the relative nature of the liquid columns?

Work done in increasing the size of a soap bubble from a radius of $3\text{cm}$ to $5\text{cm}$ is nearly (Surface tension of soap solution $=0.03{\text{N m}}^{-1}$):

A thin liquid film formed between a U-shaped wire and a light slider supports a weight of $1.5\times 10^{-2}\text{N}$. The length of the slider is $30\text{cm}$ and its weight is negligible. The surface tension of the liquid film is: