Kemija - 2009./10. ljeto - 39.

A. $\frac{1}{2}\frac{\mathrm{\Delta }c(\mathrm{D})}{\mathrm{\Delta }t}\backslash frac\{1\}\{2\}\; \backslash frac\{\backslash Delta\; c(\backslash mathrm\{D\})\}\{\backslash Delta\; t\}$

B. $-\frac{1}{2}\frac{\mathrm{\Delta }c(\mathrm{C})}{\mathrm{\Delta }t}-\backslash frac\{1\}\{2\}\; \backslash frac\{\backslash Delta\; c(\backslash mathrm\{C\})\}\{\backslash Delta\; t\}$

c. $\frac{1}{3}\frac{\mathrm{\Delta }c(\mathrm{A})}{\mathrm{\Delta }t}\backslash frac\{1\}\{3\}\; \backslash frac\{\backslash Delta\; c(\backslash mathrm\{~A\})\}\{\backslash Delta\; t\}$

D. $-\frac{1}{3}\frac{\mathrm{\Delta }c(\mathrm{A})}{\mathrm{\Delta }t}-\backslash frac\{1\}\{3\}\; \backslash frac\{\backslash Delta\; c(\backslash mathrm\{~A\})\}\{\backslash Delta\; t\}$