Ответ:

  1. \(5^4-6^3+254=625-216+254=663\).
  2. \(2\cdot5^3-3^3+3\cdot54=250-27+162=385\).
  3. \(5\cdot4^3-6^3+3\cdot88=320-216+264=368\).
  4. \(2^3\cdot5^2-8^3-4\cdot84=200-512-336=-648\).