Answer:
For a: The reaction is a type of synthesis reaction.
For b: The reaction is a type of double displacement reaction
For c: The reaction is a type of combustion reaction.
Step-by-step explanation:
The given chemical reaction is:
![Ca+Br_2\rightarrow CaBr_2](https://img.qammunity.org/2020/formulas/chemistry/college/kejsndavdz29ph0ener21le9zjplk8min8.png)
The above reaction is a type of synthesis reaction because calcium and bromine are combining in their elemental state to form a calcium bromide compound.
The given chemical reaction is:
![Ca(OH)_2+2HBr\rightarrow CaBr_2+2H_2O](https://img.qammunity.org/2020/formulas/chemistry/college/xaz5popmy1yo19o79ipwcqwhtnnjr90q2h.png)
The above reaction is a type of double displacement reaction because here exchange of ions takes place.
The given chemical reaction is:
![C_6H_(12)+9O_2\rightarrow 6CO_2+6H_2O](https://img.qammunity.org/2020/formulas/chemistry/college/suivli7ym44yql7nm307wio7aa6btwpmu2.png)
The above reaction is a type of combustion reaction because a hydrocarbon is reacting with oxygen gas to produce carbon dioxide and water molecule.