Sam is comparing the half-life of two isotopes of uranium. The half-life of Uranium-238 is 4.5×10^9 years. The half-life of Uranium-233 is 1.6×10^5 years. He computed how much greater the half-life of Uranium-238 is than that of Uranium-233, and his calculator displayed the number 2.81E4. What is this number in scientific notation?(1 point)
Responses
A. 2.81×10^4
B. 2.81+10^4
C. 2.81×10^−4
D. 4×10^2.81
4 times 10 superscript 2.81 baseline
The number 2.81E4 is in scientific notation. We can rewrite it as 2.81×10^4.
So the answer is A. 2.81×10^4.