The 'classic' arrow-head shape has 7 angles.
simple , measure them then times by 6
3
None normally although it is a 4 sided quadrilateral
An arrow head has 4 sides and it is a quadrilateral polygon
7
It depends on they type of arrowhead you have. If it is a arrowhead in the shape of a directional arrow, there are no obtuse angles. The most possible obtuse angles is 1.
A head of a arrow is the pointed end.
3 corners
an arrow has 180 degrees
1
The head of a vector arrow represent the time traveled