(d) $B = 5A^{2}$ $\Rightarrow \det(B) = \det\left( 5A^{2} \right) = 5^{3}\left\lbrack \det(A) \right\rbrack^{2}$ $= 125(6)^{2} = 4500\ \ \ \ \ \lbrack given\det{A = 6\rbrack}$
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.