CLASS 7 COMPUTER SCIENCE NOTES

COMPUTER NOTES FOR CLASS 7

Chapter 2 Formula and Functions in MS Excel 2010

Exercise B

1.  What do you understand by AutoSum?

Ans:     AutoSum is a function in a spreadsheet program like Ms Excel. This function inserts a formula in the selected cell that adds the numbers in the column above it. It sets the range of the cells by looking for numeric data above the selected cell.

2. What is a cell address? In how many ways can a cell address be given?

Ans: A cell address is also called cell reference. This address is an alphanumeric value used to identify a specific cell in a spreadsheet. Each cell reference contains one or more letters followed by a number. The letter or letters identify the column and the number represents the row. A cell address can be given in three different ways, i) Absolute ($V$13), 2) Relative (V13) or 3) Mixed ($V13 or V$13).

3. What are functions in Excel? How many types of functions do you know?

Ans: Functions are predefined formulas in Excel. The two types of functions discussed in this chapter are Math & Trig functions and Statistical functions.

4. How is a mixed cell address different from relative and absolute cell addresses?

Ans: A mixed cell address is one where either the column label or the row number is written as an absolute address, and the other is written as a relative address. To assign absolute to a row or column the $ sign is put in front of the column label or the row number. For example; $V13 and V$13 are mixed cell addresses. Whereas, in an absolute cell address, both the row number and the column label are written as absolute. For example; Column V and Row 13 is $V$13. And in a relative cell address, both the column label and row number are simply written side by side without any $ sign. For example; V13 or B6, which are relative cell addresses.

5. Write two examples for each type of functions you have learnt? Show the way how they can be used in Excel.

Function	Example 1	Example 2
Sum	=Sum(8,16,5)	=Sum(A1:A7)
Product	=Product(4,6,3)	=Product(D2:D7)
Quotient	=Quotient(35, 8)	=Quotient(D1, D2)
Power	=Power(3, 2)	=Power(d1, d2)
Max	=Max(36,24,39,48)	=Max(A1: D5)
Min	=Min(36,24,39,48)	=Min(A1: D5)
Count	=Count(A1, B2, A5, C5, E3)	=Count(a1 : G5)
Average	=Average(A1, B2, A5, C5, E3)	=Average(a1 : G5)

6.  Differentiate between MAX and Min functions.

Ans: The Max function is used to find the highest number from a set of numbers or series of cells. While, the Min function is used to find the lowest number from a set of numbers or series of cells

7. Write the steps to use AutoSum in Excel.

Ans:  To use AutoSum in Excel, select a cell next to the numbers you want to sum or to sum a column, select the cell immediately below the last value in the column. Now, click the AutoSum button on either the Home or Formulas tab and press the Enter key to complete the formula.

8. Define function argument.

Ans: The data entered while using a function is known as function argument.

Chapter 1 Computer Software and Language

Exercise G

1. What is the function of the operating system?

Ans: The functions of the operating system are to control and organize the working of a computer. It controls and manages the memory and storage. It boots up the computer and gets it ready to accept input, helps and aids the processing and displays the desired output. It maintains network communication, manages network devices and communicates with hardware devices connected locally.

2. What is general purpose software? Give examples.

Ans: General purpose software refers to application software which is used for a variety of tasks. Such software is not made for any particular type of business or industry. Instead, it is used for commercial as well as non-commercial purposes. It works in the same way for all the users working on that software. However, each user will make use of it differently. Ms Word, Coral Draw and Adobe Flash are some examples of general purpose software.

3. Write a short note on system software and its various types.

Ans:  System software refers to software that is used to operate and control the computer hardware. It also acts as a platform for running the application software. The different types of system software are Operating System, Device Drivers, Utility Programs and Language Processors.

4. Differentiate between interpreter and compiler.

Ans: Both compilers and interpreters are used to convert a program written in a high-level language into machine code which can be understood by computers.  However, there are some differences which are listed below.

Interpreter	Compiler
i) It translates the program line by line.	i) It translates the whole program at once.
ii) Its execution is slower.	ii) Its execution is faster than interpreter.
iii) It generates errors line by line for each line.	iii) It generates errors for the whole programs at once.

5. Describe briefly the generation of computer languages.

Ans: The generations of computer languages also called Programming languages have been developed over many years and can broadly be divided into five generations. Each progressive generation of development made the programming language more user-friendly, easier to use, more powerful, reliable and robust. The five phases of development, referred to as the generations of computer languages are as follows;-

(i)    First generation languages (Machine Language)

(ii)   Second generation languages (Assembly Language)

(iii)  Third generation languages (High Level Language)

(iv)  Fourth generation languages (4GLs)

(v)   Fifth generation languages (Artificial intelligence language)

(i) First Generation Languages: First Generation Languages are Machine Language which is the most basic and lowest level of computer language. It is the first programming language and is the only language that a computer can understand. Machine language programs are executed very quickly.

(ii) Second Generation Languages: Second Generation Languages are low-level Assembly Language. They have the same structure and set of commands as that of machine languages. But, it enables the user to use common names in place of 0s ad 1s. Each computer has its own Assembly Language. This language was more commonly used for video editing and gaming. This language supported video editing and gaming.

(iii) Third Generation Languages: Third Generation Languages are High Level Languages that are closer to human language. It is easier to read and write code that can run on any type of computer as it is not computer specific. C, Java and Visual Basic are some examples of High Level Languages.

(iv) Fourth Generation Languages: Fourth Generation Languages are considered Very High-level Programming Languages. These languages were designed and developed to reduce the time, cost and effort needed to develop software applications.

(v) Fifth Generation Language: The Programming Language of this generation is under constant development. The main field of this generation is Artificial Intelligence. Once programmed, these languages will make the computer solve a given problem without a programmer in future. These are aimed for future progress and are being implemented in the development of robots. In this generation of language the user will be able to communicate with the electronic gadget in a simple and easy manner. Some examples of such technology in its initial stages are Alexa by Amazon, Siri by Apple and Google Assistant.