In solid linear thermal expansion value of coefficient is 2×10 -⁵ K-¹. What value in volume thermal expansion

A ) 2 x 10-⁵ K-¹

B ) 6 x 10-⁵ K-¹ ✅

C ) 8×10-⁵ K-¹

D ) 18×10-⁵ K-¹