Not quite right, but close.  The speed of light varies slightly depending upon the medium it is
passing through.  The figure you normally hear quoted is the speed of light in a vacuum.

I do agree that how fast the heat in the vehicle rises is more important than the final temp.

Bill in the Southwest

----- Original Message -----
From: "Doug Demarest" <dougdemarest@YAHOO.COM>
>
> I've been enjoying reading the discussion of window
> tinting and transmittence of uv light, etc.  I
> disagree on a couple of things, one on principal only.
>  Light most definitely does not slow down. You can
> always count on light to go exactly the same
> speed--ie, the speed of light.