Three vectors ` vecA , vecB , vecC ` are shown in the figure angle between (i) ` vecA and vecB (ii) vecB and vecC ,(iii) vecA and vecC`

Explanation

To find the angle between two vectors we cannect the tails of the two vectors vectors we can shift ( such that trails of ` vecA ,vecB and vecC ` are connected as shown in figure
Now we can easily observe that angle between ` vecA and vecB ` is ` 60^@ , vecB and vecC ` is `15^@ ` and between ` vecA and vecC " is " 75^@`