25
Type in none
Stars are spherical bodies and have no sides nor corners.
there are so many that it would be impossible to find the total amount of stars because all stars die and become reborn
Incalcuable
An unfathomable amount.
An actual star (that is, one that is in space), doesn't really have any corners since it's a big ball of gas. If you mean the traditional star shape, they generally have 5 points. There are such things as 4 pointed stars. The Star of David, a traditional Jewish symbol, has 6 points.
Impossible to answer because they are dim stars so we can only see the close ones.
30 questions
It's difficult or impossible to answer because planets have been discovered going round a few nearby stars, but the number of external solar systems could be very high.
less then one
Probably around 7 or 8
billions and millions in the whole of space