Evaluate the expression: v ⋅ w given the vectors: r = < 8, 1, -6> ; v = < 6, 7, -3> ; w = < -7, 5, 2> explain answer

The dot product is a scalar that is the sum of the product of the corresponding components.
For example,
<x1,y1,z1>.<x2,y2,z2> = x1x2+y1y2+z1z2  (scalar).

For v<6,7,-3> and w<-7,5,2>
we have
v.w=<6,7,-3>.<-7,5,2>=6(-7)+7(5)+(-3)(2)=-42+35-6=-13

The answer would be c