Ответ:\((9b)^{1.5}=9^{1.5}b^{1.5}=27b^{1.5}\).\(\dfrac{27b^{1.5}b^{2.7}}{b^{4.2}}=27b^{1.5+2.7-4.2}=27b^0=27\).Ответ: 27.