Please help. On a winter day in Alaska, the temperature at noon was -0.6°C. From noon to 3:00, the temperature increased by 1.2°C. From 3:00 to 6:00, it dropped 0.4°C, and from 6:00 to 9:00, it decreased by 0.6°C. What expression shows the temperature in °C at 9:00 p. m.?
1. -0.6 + 1.2 + (-0.4) + (-0.6)

2. -0.6 + 1.2 – (-0.4 – 0.6)

3. -0.6 + 1.2 – (-0.4) – (-0.6)

4. 1.2 – (-0.4 – 0.6)