What shall be the value when 0.7 is divided by 350?

For different sets of datasets X and Y. correlation coefficient between X and Y, that is R and standard deviation of X and Y, that is, S(X) and S(Y) are given in A-D below. Estimate the covariance between X and Y for each dataset and arrange in ascending order.
A. R= 0.5,     S(X)= 8,     S(Y)= 10
B. R= 4/7,     S(X)= 7,     S(Y)= 9
C. R= 0.7,     S(X)= 12,     S(Y)= 5
D. R= 19/42, S(X)= 14,     S(Y)= 6
Choose the correct answer from the options given below:

Arrange the following fractions in increasing order:
A. $$\frac{7}{11}$$​​

B. $$\frac{11}{7}$$​​

C. $$\frac{9}{13}$$​​

D. $$\frac{13}{21}$$​​

Choose the most appropriate answer from the options given below:

If $$\bar{X}$$ is the mean of $$x_1, x_2, x_3, \dots, x_n$$, then for $$a \neq 0$$,  the mean of $$(a x_1, a x_2, a x_3, \dots, a x_n$$, $$\frac{x_1}{a}$$, $$\frac{x_2}{a}$$, $$\frac{x_3}{a}$$,....$$\frac{x_n}{a}$$) is:

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