%% 
digits(100)

%%
Pi = vpa('pi');

%%
repose = tan(34*Pi/180)

%%

c = Pi * repose / 3

%%

V = vpa('3.6')

%%

r = (V/c)^vpa('1/3')

c*r^3

%%

dVdt = 0.001

%%

drdt = dVdt / (3 * c * r^2)

%%

drdt * 3600

%%

h = repose * r

%%

dhdt = repose * drdt

dhdt * 3600