What is (2.1×103)+(3.4×102)(2.1 \times 10^3) + (3.4 \times 10^2)(2.1×103)+(3.4×102)?
5.5×1055.5 \times 10^55.5×105
2.44×1032.44 \times 10^32.44×103
5.5×1025.5 \times 10^25.5×102
2.1×1052.1 \times 10^52.1×105