deletions | additions       diff --git a/According_to_citet_To_2013_the__.tex b/According_to_citet_To_2013_the__.tex  index a44adff..f09c4e8 100644  --- a/According_to_citet_To_2013_the__.tex  +++ b/According_to_citet_To_2013_the__.tex 
...
Using the computer in education and recreation is common nowadays. In the study of \citet{Robic_2015}, it is noted that ICT can be great motivational tool for teaching and learning, especially computer games can be great motivational tool. Some games also include physics on it, namely Angry birds. The researchers would want to incorporate the physics projectile model because of the game concept that the researchers wants to design. Projectile motion is a case of motion which can be described as motion in two dimensions, in vertical and horizontal way. In the case of the game the air resistance can be neglected because the game was not designed to include air resistance in projectile motion. The projectile motion is then applied to the garbage in the game play. The following significant formulas are the formulas that the researchers will be using in the game play,   \begin{equation*}y_{height}=(v_{0y}\sin\theta)t-\frac{1}{2}gt^{2}+y_{start},\tag{1}\end{equation*}  where \begin{equation*}{ \begin{}{  y }_{ start }\end{equation*} }\end{}