Always draw a diagram first to help with clarity.Correct use of Sine Rule:sin(A)/BC = sin(C)/ABTherefore sin(C) = ABsin(A)/BC sin(C) = 20sin(70)/100 sin(C) = 0.188 (rounded to 3 Significant Figures) C = arcsin(0.188) = 10.83 (rounded to 2 decimal places)