Hello everyone! I have some questions here to ask.... I hope anyone could help me here. Here are the following. 1. How would the presence of air bubbles or water in mercury affect the results in a "J-tube" experiment? 2. Why does food cook faster in a pressure cooker than in an aluminum ware? 3. There are times when the water boils at less than 100 deg. celsius, especially at mountainous regions. Why is it?