Q7. | The type of valve which is provided to control the flow of water in the distribution system at street corners and where the pipe lines interest is : |
Q8. | The effective size of sand particles used in slow sand filters is : |
Q9. | The process in which chlorination is done beyond the break point is : |
Q10. | The most common cause of acidity in water is : |
Q11. | Which of the following methods of analysis of water distribution system is most suitable for long and narrow pipe system ? |
Q12. | The dissolved oxygen level in natural unpolluted water,at normal temperature is found to be of the order of : |