What is the difference of scientific notation. 0.00067 - 2.3 x 10^-5

a. 6.47 x 10⁻⁴

b. 6.47 x 10⁻⁵

c. 4.4 x 10⁻⁵

d. 4.4 x 10¹

For this case we must find the difference of the following expressions:

For the second expression we must run the decimal 5 times to the left, because the exponent is negative, that is:

We subtract:

Represented in scientific notation we have:

Option A

30

step-by-step explanation:

times by times

all three statements are true

step-by-step explanation:

a shipping fee of 5% is charged online with every item purchased online

first let's just take each option and calculate them based on this, to see if the answers matched

keith buys a 40 dollar book

40 x 0.05 = 2

therefore there will be a two dollar fee on keith's book

40 + 2 =42

the first statement is true

a chair costs $80

80 x 0.05 = 4

80 + 4 = 84

the second statement is true

george buys a 20 dollar calculator

20 x 0.05 = 1

20 + 1 = 21

the third statements are true

all three statements are true