Construct a symmetric matrix with the following eigenvectors and eigenvalues, or explain why none exists: (a) 1

Construct a symmetric matrix with the following eigenvectors and eigenvalues, or explain why none exists:
(a) λ1 = 1, v1 = (3/5, 4/5)T,
λ2 = 3, v2 = (-4/5, 3/5)T
(b) λ1 = -2, v1 = (1, -l)T,
λ2 = l, v2 = (1, l)T
(c) λ1 = 3, v1 = (2, -l)T,
λ2 = -1, v2 = (-1, 2)T
(d) λ1 = 2, v1 = (2, l)T
λ2 = 2, v2 = (1, 2)T