The first steps in the radioactive decay of 257 Uuh involves the rapid and successive emission of 2 alpha particles. [Note: Uuh is the symbol for ununhexium, which is element number 116.] An original sample of 0.405 micrograms of 257Uuh yielded 0.238 micrograms of the appropriate product nuclide after 42.72 microseconds of decay had occurred. What is the half-life (microseconds) for 257Uuh