By sketching their graphs or otherwise, find the range of these functions given the domain. State whether each function is a one-to-one function or a many-to-one function.

a) f: x ↦ 2x + 1, x ∈ R

b) g: x ↦ x² − 4, x ∈ R, −3 < x < 3

c) h: x ↦ −x³, x ∈ R, −2 < x ≤ 1

d) f: x ↦ (x − 3)², x ∈ R, x ≥ 4

e) g: x ↦1 − 2x, x ∈ R, 1≤ x ≤ 3

f) h: x
↦(x + 1)², x ∈ R, x ≥ −1