README-en.md edited online with Bitbucket

README-en.md

 
 ## Laboratory Session:
 
-### Exercise  1: Implement the functions that operate the buttons for drawing lines
+### Exercise  1: Implement the Functions that Operate the Buttons for Drawing Lines
 
 ####Instructions
 
 **Figure 5** - (a) A drawing with a white background and red dots. (b) When the user clicks on the right diagonal line button (`DiagonalRight`) and clicks the cell shown, (c) a right diagonal line that expands towards the top to the right and towards the bottom to the left of the cell clicked is drawn, until it finds a cell with a different color from the color of the background. 
 
 
-### Exercise 2: Implement the functions that operate the buttons for drawing squares, triangles and circles. 
+### Exercise 2: Implement the Functions that Operate the Buttons for Drawing Squares, Triangles and Circles. 
 
 Now, you will implement the functionality to draw squares, circles and triangles. The **size** of the figure drawn will depend on the size selected on sliding bar in the interface.
 
 
 **Figure 7** - Triangles of size 1 (green), 2 (red), 3 (blue), and 4 (yellow). In each case, the user clicked the center of the base of the triangle. 
 
-#### 2c: Círculos
+#### 2c: Circles
 
 Congratulations! You got to the most difficult part: circles! Here you’ll need to use your mathematical skills… we hope that you did well on your pre-calculus class...
 
 
 **Figure 8** - Circles of size 1 (green), 2 (red), 3 (blue), and 4 (yellow). In each case, the user clicked the center of the circle. 
 
-**Help producing circles:**
+**Help Producing Circles:**
 
 First of all, you need to understand that the terms associated with a circle that has an equation: $x^2+y^2=r^2$. For example, consider a circle with radius $r=1$. The equation $x^2+y^2=1$ tells us that every point $(x,y)$ that satisfies the equation is a point in the circle’s *circumference*. The expression for a *filled* circle is : $x^2 + y^2 <=r^2$. A filled circle, of radius $r=1$ has the expression  $x^2 + y^2 <= 1$, which says that every point $(x,y)$ that satisfies $x^2 + y^2 <= 1$ is a point in a filled circle.
 
 
 
 
-### Exercise 3: Implement the function that fills the figures using recursion. 
+### Exercise 3: Implement the Function that Fills the Figures using Recursion. 
 
 In this exercise you will implement the functionality to fill the color of the figures.One of the more convinient ways to express the algorithm to fill the figures is using recursion. A basic recursive algorithm (but it’s pretty weak) is found in Wikipedia: