<image>The following statistics graph shows the temperature changes as Wang Gang boils a kettle of water. Please fill in the blanks based on your observations from the graph.
(1) The water temperature before heating is ____℃;
(2) After heating for 6 minutes, the water temperature is ____℃;
(3) It took ____ minutes to heat the water to 85℃;
(4) It took ____ minutes to boil the kettle of water.
