Contestable markets

Thanks to tutor2u for this
http://www.tutor2u.net/economics/reference/contestable-markets-1?utm_medium=email&utm_campaign=Economics%20daily%20digest%20Fri%2019th%20February%202016&utm_content=Economics%20daily%20digest%20Fri%2019th%20February%202016+CID_c42247d15d72f50bbefe4755dec974eb&utm_source=CampMonitor&utm_term=Contestable%20Markets%20Study%20presentations%20How%20does%20the%20threat%20of%20competition%20affect%20a%20firms%20behaviour