An angel investor is analyzing the growth potential of a startup that follows a polynomial revenue model given by \( R(t) = 4t^3 - 3t^2 + 2t - 5 \), where \( R \) is the revenue in millions of dollars and \( t \) is time in years. Determine the time at which the revenue reaches its maximum, assuming the model holds for \( t \geq 0 \). - Groen Casting