Questions

 It is a strange sequence. Each number describes the resemblance of the previous one, except the first one.

11 describes the previous '1' which contains one '1'

21 describes the previous '11' which contains two '1'

1211 describes the previous '21' which contains one '2' and one '1'

111221 describes the previous '1211' which contains one '1', one '2' and two '1'.

So the next sequence will be 312211, that is the previous '111221' contains three '1', two '2' and one '1'.

Although it is less accurate than adding up individual costs from the WBS, it is less time consuming. The trade-off is accuracy. Answer A is incorrect because to do a more accurate cost estimate, you need to delve into details. Answer C is tempting also, and possible, except we don't really know if the project in question can use perametric modeling . Answer D is incorrect because it takes the most time, but it is most accurate.

Rajasthan to become first state to legalise wearing masks in public places. State to make masks wearing mandatory to prevent the spread of Covid19.