Which of the following statements regarding the property of hard water is/are correct? 1. Temporary hardness of water is due to the presence of soluble magnesium and calcium hydrogen carbonate. 2. Temporary hardness of water can be removed by boiling. 3. Calgon’s method is applied to remove temporary hardness of water. 4. Permanent hardness of water is removed by Clark’s method. Select the correct answer using the code given below:

For election to the Lok Sabha, a nomination paper can be filed by

Miscellaneous · Easy

In a month if the seventh day is three days earlier than Saturday,then the nineteenth day of the month will be a

Miscellaneous · Easy

Which among the following events happened earliest ?

Miscellaneous · Easy

An 80-litre solution of alcohol and water has 75% alcohol. How much water (in litres) must be added to bring down the concentration of alcohol to 60%?

Miscellaneous · Easy