clean up

docs/Getting-Started-with-Balance-Ball.md

 You can create new Brain assets by selecting `Assets -> 
 Create -> ML-Agents -> Brain`. There are 3 types of Brains. 
 The **Learning Brain** is a Brain that uses a trained neural network to take decisions.
-When the `Control` box is checked in the Brains property under the **Broadcast Hub** in the Academy is checked as `Control`, the external process will be take over making decisions for the agents
+When the `Control` box is checked in the Brains property under the **Broadcast Hub** in the Academy, the external process will be take over making decisions for the agents
 and ultimately generate a trained neural network. You can also use the
 **Learning Brain** with a pre-trained model.
 The **Heuristic** Brain allows you to hand-code the Agent's logic by extending