Numbers may be entered in several formats - including scientific notation and numerical expressions. WebAssign uses standard scientific or "e" notation for "times 10 raised to the power." For example, 1e3 is the scientific notation for 1000.

You cannot have a space in a number.

You cannot substitute the letter O for zero or the letter l for 1.

You cannot include the units in the number unless specifically asked for.

You can include the sign + or - of the number.

Which of the entries below will be interpreted as numbers? (Select all that apply.)

1.56e-9 3.25E4 2.54 m 1.56 e-9 1.9435 - 4.99 1.23 inches

Following entries can be regarded as numbers:

1.56e-9

1.9435

-4.99

Explanation:

According to the given rules, only "e" can be used for show power of 10. Furthermore, using space between numbers and including units (without justification) are not allowed. Under these rules let us consider each number given.

1) 1.56e-9

This satisfies all three conditions given above and hence, is a number. Simplified value is

2) 3.25E4

As we can only use "e" for exponents, use of "E" is wrong, therefore this entry cannot be considered as a number.

3) 2.54 m

Here a space and a unit "m" (meter - unit of length) is used and therefore this entry cannot be considered as a number.

4) 1.56 e-9

Here a space is used due to which this value is not declared a number.

5) 1.9435

This again satisfies all conditions and therefore is a number.

6) - 4.99

This is also a number as the use of + or - sign is allowed.

7) 1.23 inches

Here a space and a unit "inches" (unit of length) is used again and therefore this entry is also not a number.