If sec θ + tan θ + 1 = 0, then sec θ − tan θ is equal to :

1. −1

2. 0

3. 1

4. 2

If a cot θ + b cosec θ = p and b cot θ + a cosec θ = q, then p² − q² is equal to :

1. a² − b²

2. b² − a²

3. a² + b²

4. b − a