A graph of volume of hydrogen released vs time for the reaction between zinc and dil. HCl is given in figure . On the basis of this markt the correct options.
A. Average rate upto 40 seconds is `(V_(3)-V_(2))/(40)`
B. Average rate upto 40 seconds is `(V_(3)-V_(2))/(40-30)`
C. Average rate upto 40 seconds is `V_(3)/40`
D. Average rate upto 40 seconds is `(V_(3)-V_(1))/(40-20)`