Question

Short answer

Yes, the water level will attain the threshold limit of the fluoride ion.

Step-by-step solution

Step-by-Step SolutionStep 1: Concentration of fluoride ion

Level of Fluorides.

Recommended by the U.S. Public Health Service for Fluorides ion is $5\times {10}^{-5}$.

And after doing the concentration of fluoride ion, we saw that water would attain the level that was recommended by the U.S. health services as it was greater than that:

$1.4\times {10}^{-4}\mathrm{M}>5\times {10}^{-5}\mathrm{M}$

Therefore,

The water supply will attain the level of fluoride ion recommended by the U.S. Public Health service because

$1.4\times {10}^{-4}M>5\times {10}^{-5}M$