I've always known sprite and similar lemon flavored soft drinks to be lemonade, though there is a lime version.
I'm sure I remember seeing lemonade on sprite packaging when I was younger, and it looks like Google agrees with my memory. Not sure why these other guys are arguing with you.
Obviously the same for all the other brands as well (Schweppes lemonade is very much a carbonated soft drink).
In well designed urban areas, where lights are synchronized I would expect a change in speed limit without changes in traffic light logic to increase time spent waiting at lights.
This has a knock on effect in heavy traffic areas as a car in front stopping might take 10 seconds to take off when the signal changes, but each car behind them has the cumulative delay of each driver in front, so a 10 seconds delay for the first car would likely be closer to a full minute for the fifth car.
I'm not sure that this extra time spent idling would be enough to undo the reduction in emissions due to lowering speed limits (more likely for EVs I imagine), but if implemented sloppily (as has been the case every time I've ever seen a speed limit on a road reduced), it does add significant time to commutes during busy times and should actually be thought through properly, with other changes to optimize traffic because of it, fully considered.
A far more effective and cheaper way of reducing emissions is invest in reliable and affordable public transit options, or better yet safe cycle paths.