Compute (4.0×105)×(2.5×103)(4.0 \times 10^5) \times (2.5 \times 10^3)(4.0×105)×(2.5×103) and express in scientific notation.
1.0×1091.0 \times 10^91.0×109
1.0×1081.0 \times 10^81.0×108
10×10810 \times 10^810×108
6.5×1086.5 \times 10^86.5×108