A bank 'xyz' wants to know about its popularity among the residents of a city 'ABC' on the basis of number of bank accounts each family has and the average monthly account balance of each person. Briefly describe the steps to be taken for collecting data and what results can be checked through processing of the collected data.

Identify type of data being collected/generated in the following scenarios:

1. Recording a video
2. Marking attendance by teacher
3. Writing tweets
4. Filling an application form online

A school teacher wants to analyse results. Identify the appropriate statistical technique to be used along with its justification for the following cases:

1. Teacher wants to compare performance in terms of division secured by students in Class XII A and Class XII B where each class strength is same.

2. Teacher has conducted five unit tests for that class in months July to November and wants to compare the class performance in these five months.

Suppose annual day of your school is to be celebrated. The school has decided to felicitate those parents of the students studying in classes XI and XII, who are the alumni of the same school. In this context, answer the following questions:

1. Which statistical technique should be used to find out the number of students whose both parents are alumni of this school ?

2. How varied are the age of parents of the students of that school ?