If $$p\left(\frac{1}{q}+\frac{1}{r}\right), q\left(\frac{1}{r}+\frac{1}{p}\right), r\left(\frac{1}{p}+\frac{1}{q}\right)$$ are in $$\mathrm{AP}$$, then $$p, q, r$$

$$n$$th term of the series $$1+\frac{3}{7}+\frac{5}{7^2}+\frac{1}{7^2}+\ldots$$ is

If $$A=\{1,2,3, \ldots, 10\}$$, then number of subsets of $$A$$ containing only odd numbers is

If $$a_1, a_2, a_3, \ldots, a_{10}$$ is a geometric progression and $$\frac{a_3}{a_1}=25$$, then $$\frac{a_9}{a_5}$$ equals