Answer:
D
Step-by-step explanation:
Let's write each number as a decimal.
1.6 x 10⁻⁴ = 0.00016
Because multiply by 10⁻⁴ means that the decimal point of 1.6 is 4 places to the left. In the same way, we get for each option
Option A.
1.6 x 10⁻⁴ = 0.00016
1.62 x 10⁻⁴ = 0.000162
1.7 x 10⁻⁵ = 0.000017
Therefore, 0.000162 is greater than 0.00016 and they are not arranged from greatest to least.
Option B.
1.62 x 10⁻⁴ = 0.000162
1.6 x 10⁻⁵ = 0.000016
1.7 x 10⁻⁵ = 0.000017
Since 0.000017 is greater than 0.000016, they are not arranged from greatest to least
Option C.
1.6 x 10⁻⁵ = 0.000016
1.7 x 10⁻⁵ = 0.000017
1.62 x 10⁻⁴ = 0.000162
Since 0.000017 is greater than 0.000016, they are not arranged from greatest to least
Option D.
1.62 x 10⁻⁴ = 0.000162
1.7 x 10⁻⁵ = 0.000017
1.6 x 10⁻⁵ = 0.000016
Then, the correct option is D.