Answer:
In case of plants surface tension help to support the transpiration pull.
Explanation:
Surface tension is a force that hold the molecules in the surface to minimize the surface area.
During evaporation of excess amount of water from the stomata of leaves of plants by transpiration a surface tension is generated.
The generated surface tension helps to maintain the water column within the xylem tissue by the absorption of water from the soil by the roots.
I used an online calculator and got 54.22 m/s. I hope that helps
You should take note that the question is about stability. A compound is stable if it does not easily react with other elements. Hence, its reactivity must be low. As you move down the group, reactivity decreases. So, the halide at the very bottom is the least reactive. It would then be logical that the most stable conjugate base is I⁻ and the least stable conjugate base is the most reactive which is F⁻.