One day Chetan's mother developed a severe stomach ache all of a sudden. She was rushed to the doctor who suggested for an immediate endoscopy test and gave an estimate of expenditure for the same. Chetan immediately contacted his class teacher and shared the information with her. The class teacher arranged for the money and rushed to the hospital. On realising that Chetan belonged to a below average income group family, even the doctor offered concession for the test fee. The test was conducted successfully. Answer the following questions based on the above information.
(i) Which principle in optics is made use of in endoscopy?
(ii) Briefly explain the values reflected in the action taken by the teacher.
(iii) In what way do you appreciate the response of the doctor on the given situations?