characters are like letters, punctuation marks, spaces, numbers etc. in chinese it could also mean each separate character but you know ;) But don't confuse characters with words. Something with 40-140 characters is really little!
You're allowed 140 characters with or without a link.
To convert net keystrokes into words per minute (WPM), you typically divide the total keystrokes by an average word length, often estimated at 5 characters per word, including spaces and punctuation. For 140 net keystrokes, this results in 140 ÷ 5 = 28 words. If this typing took one minute, that would equal 28 WPM.
4000 characters is approximately 500 words.
about 140
740
not very many...
3000 Characters is averaged between 2,000 words to 2,980 words.(allwordphone.com/count-words-characters.htm)
not very many...
Average is 2-3 words a second, so around 140 words.
740
That will depend on the words. However, in typing for measuring speed, a word is considered to be 5 characters.