b) \(\sqrt{144}-5.\sqrt{\dfrac{16}{9}}+\left|-5\dfrac{1}{3}\right|\)
=\(12-5.\dfrac{4}{3}+\dfrac{16}{3}\)
=\(12-\left(\dfrac{20}{3}-\dfrac{16}{3}\right)\)
=\(12-\dfrac{4}{3}\)
=\(\dfrac{32}{3}\)
c) \(\dfrac{21^4}{27.\left(-343\right)}+7=\dfrac{7^4.3^4}{3^3.\left(-7\right)^3}+7=-7.3+7=-21+7=-14\)