<prompt> Translate the following text to SwahiliRule 504a authorized the Postmaster General to maintain a research and development program, and to conduct experiments to enhance the operational efficiency and economy of the postal system.  <response>: Sheria ya 504 a iliruhusu Mkuu wa Postmaster kudumisha programu ya utafiti na maendeleo, na kufanya majaribio ili kuongeza ufanisi wa uendeshaji na uchumi wa mfumo wa posta. 