Update Day_13.md

Author: darkprinx

Status/Day_13.md

@@ -4,7 +4,7 @@
 
 **Question:**
 
-***Define a class named Circle which can be constructed by a radius. The Circle class has a method which can compute the area. ***
+***Define a class named Circle which can be constructed by a radius. The Circle class has a method which can compute the area.***
 
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 ### Hints: Use def methodName(self) to define a method.
@@ -33,7 +33,7 @@ print aCircle.area()
 
 **Question:**
 
-***Define a class named Rectangle which can be constructed by a length and width. The Rectangle class has a method which can compute the area. ***
+***Define a class named Rectangle which can be constructed by a length and width. The Rectangle class has a method which can compute the area.***
 
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 ### Hints: Use def methodName(self) to define a method.