letter to Executive Engineer of the Jal Board about the water problems

Many desert plants overcome the water problem by

If an automobile engine is overheated, it is cooled by putting water on it. It is advised that the water should be put slowly with engine running. Explain the reason.

Which one of the following statements about water is false ?

Two particle execute SHM of same amplitude of 20 cm with same period along the same line about the same equilibrium position. The maximum distance between the two is 20 cm . Their phase difference in radians is