The notation 1.8E-4 represents the scientific notation for the number \( 1.8 \times 10^{-4} \), which is equal to \( 0.00018 \).
Let's analyze the options:
- -0.00018: This is not equivalent; it has a negative sign.
- 1.8 × 10 -4: This is equivalent. It represents the same value as 1.8E-4.
- 18 × 10 4: This is not equivalent. This equals \( 180 \), which is much larger than \( 0.00018 \).
- 0.00018: This is equivalent; it is the decimal form of \( 1.8E-4 \).
- 1800: This is not equivalent; it's much larger than \( 0.00018 \).
The correct answers are:
- 1.8 × 10 -4
- 0.00018