Step 1 :Find the volume of the cylinder: \(V = \pi r^2 h = \pi (5)^2 (20) = 1570.80 \mathrm{cm}^3\)
Step 2 :Find the volume of liquid A and liquid B in the cylinder: \(V_A = \frac{4}{15} V = 418.88 \mathrm{cm}^3\) and \(V_B = \frac{11}{15} V = 1151.92 \mathrm{cm}^3\)
Step 3 :Find the mass of liquid A and liquid B in the cylinder: \(m_A = \rho_A V_A = 1.05 (418.88) = 439.82 \mathrm{g}\) and \(m_B = \rho_B V_B = 1.27 (1151.92) = 1462.93 \mathrm{g}\)
Step 4 :\(\boxed{\text{Final Answer:}}\) Add the mass of liquid A and liquid B to find the total mass of liquid C in the cylinder: \(m_C = m_A + m_B = 439.82 + 1462.93 = \boxed{1900 \mathrm{g}}\)