Usually they have one baby at a time; twins are very rare.
1
a billion
yes a humpback whale is a mamale and it has babies
Useally one at a time.
1 baby or 2
1 or rarely 2
only once
humpbacks have babies by mateing
They have one calf at a time.
Most probably 1 as they are like big and that besides am not a whale nerd :)) this prob wont help but ..x
Yes
A whale shark (as far as i know) can have between two and three young. I am eleven and i totally powned this question :p