Question Discussion & Solution

49 ÷ 7 = 7,

70 ÷ 7 = 10,

91 ÷ 7 = 13,

99 ÷ 7 = 14.14

So, 49, 70 and 91 are the multiples of 7 while 99 is not a multiple of 7.

Hence, “8” will come in the place of question mark. 

The correct answer is Natural Gas.

Key Points

•  Fossil Fuel: Fossil Fuels are the fuels generated from the residues of living organisms (which remained buried under the earth for millions of years).
  • Examples: Coal, Petroleum, and Natural gas.
  • They are also known as Non-Renewable Natural Resources.​

 Additional Information

• Natural Gas: It is considered the best fuel because of the inflammable nature of its constituents(83% methane and 16%ethane).
  • It is used in the production of artificial chemical fertilizers. 
• Coke: It is obtained by the strong heating of coal in the absence of air as a residual substance. 
  • It contains 80-85% carbon.
  • Coke is used in the extension of metals as a reducing agent.
• Producer Gas: It is a mixture of nitrogen and carbon monoxide(in 2:1 ratio).
  • It is used in the manufacture of glass and for metallurgy. 

The correct answer is F2.

Key Points

• F2 function key is used to edit the content of a cell in MS-Excel.
• To enter Edit mode, we can follow any of these steps:
  • Double-click the cell that contains the data that you want to edit.
  • Click the cell that contains the data that you want to edit, and then click anywhere in the formula bar.
  • Click the cell that contains the data that you want to edit, and then press F2.

Additional Information

Some important shortcuts used in MS Excel:

• Ctrl + N Create a new workbook.
• Ctrl + O Open an existing workbook.
• Ctrl + S Save the active workbook.
• F12 Save the active workbook under a new name, displays the Save as dialog box.
• Ctrl + W Close the active workbook.
• Ctrl + C Copy the contents of the selected cells to Clipboard.
• Ctrl + X Cut the contents of the selected cells to Clipboard.
• Ctrl + V Insert the contents of the Clipboard into the selected cell(s).

Least possible diagram is:

I. Some car are Maruti. → True

II. No Ciaz is a Maruti. → False