Sam is comparing the half-life of two isotopes of uranium. the half-life of uranium-238 is 4.5 x 10^9 years. the half life of uranium-233 is 1.6 x 10^5 years. he computed how much greater half-life of uranuim-238 is than that of uranium-233, and his calculator displayed the number 2.81e4. what is this number in scientific notation?
A 2.81 x 10^-4
B 4 x 10^2.81
C 2.81 x 10^4
D 2.81 + 10^4