This is a True or False question

a) For every square matrix A, if every entry of A is nonzero, then A is invertible. b) Whenever A, B and C are invertible n x n matrices, we have (ABC)-1 = A-1B-10-1. c) If A is a square matrix such that det(A) = 0, then Ax = 0 has nontrivial (nonzero) solutions. d) For all n x n matrix A, det(A?) = det(A)2. For all square matrices A of any order, det(5A) = 5 det(A)