Answer: B
Step-by-step explanation:
1) First find the weight of the elephant: 1.1 * 10^4 = 11,000
2) Then find the weight of the giraffe: 2.1 * 10^3 = 2,100
3) Then subtract the weight of the giraffe from the weight of the elephant
11,000 - 2,100 = 8,900
4) And there is your answer 8.9 * 10^3 = 8,900