Final answer:
Option B (3.99 × 10^(-6)) is the smallest number among the given options. Numbers with smaller negative exponents in scientific notation represent smaller values, and B has the smallest exponent.
Step-by-step explanation:
To find the smallest number among the given options, we need to understand the notion of scientific notation for both very large and very small numbers. Scientific notation is a way to express numbers as the product of a coefficient (between 1 and 10) and a power of 10. Comparing the exponents of the given numbers can provide a quick understanding of the relative sizes of these numbers.
Let's look at the options:
A. 4.4 × 10^(-5)
B. 3.99 × 10^(-6)
C. 2.6 × 10^2
D. 1.85 × 10^3
Numbers with negative exponents represent values less than one. Among them, a smaller exponent value indicates a larger denominator and therefore a smaller number. Conversely, positive exponents represent numbers greater than one, with larger exponent values indicating bigger numbers.
From the options, we see that:
Options A and B are less than one since they have negative exponents.
Option B has a smaller exponent (-6) compared to option A (-5), making B smaller than A.
Options C and D are greater than one with positive exponents, and their values are larger than those of A and B.
Therefore, option B, 3.99 × 10^(-6), is the smallest number among the given options.