Is Acetone Save For Vinyl Windows?

No - acetone is a solvent for vinyl.

Getting an engineering degree must do it. I was watching shows on the Science Channel showing building screw ups. Some of the mistakes are just plain stupid. A decimal point in the wrong place, not converting from English to metric, etc. The second one caused a satellite to crash on the moon.

And caused the "gimli glider" incident - - - -

I remember being shown a video of the Tacoma Narrows Bridge in a freshman class with the advice 'this is not how you design a bridge'.

Do I have it right that something shaped like an inverted airplane wing is put under the bridges now to minimize wind effect?

I don't know about that but they do pay a lot more attention to the wind effect:

That's the replacement and it hasn't fallen into the Sound (yet).

That's the original. The new one appears to have a lot more truss work under the deck. That was one difference between that and the Golden Gate or George Washington, both of which are longer. The trusses for the Tacoma bridge were enclosed in concrete and split the airflow rather than just letting it blow through.

For trivia, Robert Resnick was a professor at RPI so we of course used the Resnick & Halliday physics text. Resnick's explanation at the time was natural resonance like the old marching soldiers breaking cadence when crossing a bridge. Later research points to a more complex answer.

Science can't even get it right when saying why a bridge fell down :) Of course in that same textbook it assumed the coefficient of friction could not exceed 1, which limited the times for, say, a quarter mile. Our TA, who drove a Corvette and was a car nut, took great glee in pointing out the fuel dragsters were beating that theoretical limit. Back to the drawing board on that one too.