6 - has to be a begonia ...
13 - Z and Q
16 - around 2250 from memory .... "Babylon 5" was one of the best sci-fi soap operas produced for TV; arguably better than the Star Trek franchise, it ran for 4 or 5 seasons. Right up there with the likes of "Farscape" and "Alien Nation" .....
<sigh> they simply don't make brilliant sci-fi like that these days. Some excellent support actors, my favorites being the flamboyant Andreas Katsulis and Peter Jurasik as two alien ambassadors G'Kar and Londo Molari, who were always sparring off with each other. Forget who broadcast it now, was it Channel 5? I guess I must have seen pretty much every episode ....