Solve the following cryptarithm:

   E A R T H
       A I R
     F I R E
+  W A T E R
------------
 N A T U R E




------------------------------------------------------------



Here is the answer:

The following alphametic puzzle:

 EARTH
   AIR
  FIRE
+WATER
------
NATURE

has 1 solution.

It is:

 67432    A=7 E=6 F=8 H=2 I=0 N=1 R=4 T=3 U=5 W=9 
   704
  8046
+97364
------
173546