The amount of time it takes for an amount of a specific isotope to decay to half the original amount. a. absolute-life c. half-life b. relative-life d. specific-life

Which revelation resulted from the observation of the spectrum of different galaxies? a. there were more galaxies whose spectrum was blueshifted b. there were no galaxies whose spectrum was redshifted c. there were more galaxies whose spectrum was redshifted d. there were no galaxies whose spectrum was blueshifted

Most tornadoes carry winds speeds in a range of km per hour

What are two australian geographical features that hindered early exploration? western plateau gulf of carpentaria great barrier reef great dividing range