12 men can do a work in X days. 20 women can do the same work in (X -1) days. 15 men can do the work in y days while 30 women can do it (Y- 2) days . Find the value of X. 

Direction: In these questions, a part of the sentence is given in bold. Below are given alternative to the bold part at (A), (B) and (C) which may improve the sentence. Choose the correct alternative. In case no improvement is needed you answer is (D).
Q.10. Many of man would welcome to opportunity

In 1831, electricity became viable for use in technology when ________ created the electric dynamo.

B is father of Q. B has only two children. Q is the brother of R. R is the daughter of P. A is the granddaughter of P. S is the father of A. How is S related to R?

After wound or cut in body blood coagulates through:

Gunpowder consists of a mixture of :