It is difficult to cook rice

Solution

On a mountain top the air pressure is a little lower. At higher elevations, water boils at a little lower temp than 100 degrees C. On a mountain top cooking takes longer, because it is like cooking on medium heat, instead of leaving the burner on high. Either way it will cook, one will take longer than the other. The boiling point of water in mountainous areas is lower because of a decreased air pressure (compared to sea level) at higher altitudes.