How wide and high is 50 seater buses?

Answer 1

In the UK:

A 50 seater bus is usually 2.5m (8'21/2") wide (though more recent buses are occasionally slightly wider at something like 2.55m or 8'4")

As to height, they have gradually been getting higher. The vehicle I learnt in was about 3.2m (10'6"), I then drove one 3.5m (11'6") high regularly (before the double deck, 71 seater, at 4m or 13'2" high I now drive) and there are others at 3.66m (12') or [slightly] higher that are single deck, 53 (or less, with tables) seaters.

Length wise, the buses are usually 12m (39'7", usually rounded to 40') long, though more recent ones are 13m (42'8") long.