If is the angle between line whose ratios are a1, b1, c1 and the plane ax + by + cz + d = 0 then cos = ( frac {a1a2.b1b2.c1c2}{ sqrt {a1^2+b1^2+c1^2} sqrt {a2^2+b2^2+c2^2 }} ).

• A. True
• B. False