a) $-5.|\dfrac{-25}{3}|+(-7)^2.\sqrt{\dfrac{100}{25}}-325^0.\sqrt{(\dfrac{-3}{5})^2}$
$=-5.\dfrac{25}{3}+49.2-1.\dfrac{3}{5}$
$=\dfrac{-100}{3}+98-\dfrac{3}{5}$
$=\dfrac{-500}{15}+\dfrac{1740}{15}-\dfrac{9}{15}=\dfrac{1231}{15}$
b) $\dfrac{7}{3}.\sqrt{\dfrac{4}{49}}-\dfrac{3}{5}.|\dfrac{-5}{9}|-325.(\dfrac{-4}{325})$
$=\dfrac{7}{3}.\dfrac{2}{7}-\dfrac{3}{5}.\dfrac{5}{9}+4$
$=\dfrac{2}{3}-\dfrac{1}{3}+\dfrac{12}{3}$
$=\dfrac{13}{3}$
c) $\dfrac{4}{5}.\sqrt{\dfrac{25}{16}}+\dfrac{7}{8}.|\dfrac{-8}{7}|-(-3)^2.\sqrt{\dfrac{3}{27}}$
$=\dfrac{4}{5}.\dfrac{5}{4}+\dfrac{7}{8}.\dfrac{8}{7}-9.\dfrac{1}{3}$
$=1+1-3=-1$