Answer:
Definition:
A horizontal intergration occours when a firm takes over or merges with another firm in the same stage of production, Producing similar or same products .
+Advantages
+Achieave Greater Economies of Scale
+Increase its market share
+Reduction in average cost as a result of rationalization
-Disadvantages
-Increase in average cost -if the company is too large and experiencing dis economies of scale
-The two companies maybe located some distance apart,although advances in ICT are reducing this problem.
-There is initially likely to be some extra cost involved in seeking to harmonize,for instance,wage rates and accounting systems in the two companies
I hope this will help you :D