Assuming the given unit hydrograph is a $40$ minute unit hydrograph, calculate a direct runoff hydrograph for a storm that had the following excess rain volumes $($inches$)$ in successive $40$ minute intervals: $0\mathrm{.}33,0\mathrm{.}22,1\mathrm{.}13,0\mathrm{.}84,0\mathrm{.}51,0\mathrm{.}17.$

Assuming the given unit hydrograph is a $20$ minute unit hydrograph, develop a $120$ minute unit hydrograph for this watershed.