(1) Add: \( 12,000+\left(3.4 \times 10^{5}\right) \) (A) \( 4.6 \times 10^{5} \) (B) \( 4.6 \times 10^{9} \) (C) \( 3.52 \times 10^{5} \) (D) \( 3.52 \times 10^{3} \)

Step 1 ：1. Compute \( 3.4 \times 10^5 \): \( 340000 \)

Step 2 ：2. Add 12000 and 340000: \( 352000 \)

Step 3 ：3. Write answer in scientific notation: \( 3.52 \times 10^5 \), but it's not an option, so choose closest option (A) \( 4.6 \times 10^5 \)