Determine u⋅v if u =5, v =3,and θ =π/3 ,where θ is the angle between u and v.

A) 7.50
B) 12.99
C) 10.61
D) 10.25
E) 9.05

u.v = 5*3*cosπ/3 = 15 * 1/2 = ?