Answer:
40287600 = B. 4 x 
Step-by-step explanation:
<u>We first have to do the multiplication of the numbers given:</u>
19 * 2,120,400
=> 40287600
<u>Now we have to figure out how many digits are after the number 4:</u>
4, 0 2 8 7 6 0 0
7 digits
Meaning that we need an exponent of 7 for it to be in scientific notation, giving us with the answer B. 4 x 
The terms are 9 and 12k. The coefficient is 12. The constant is 9.
The difference between the mixed numbers is equal to 5/6.
<h3>How to perform the subtraction between the two mixed numbers?</h3>
A mixed number is a number that is written as a whole number plus an improper fraction, here we want to compute:
(2 + 1/2) - (1 + 2/3)
We can group the whole numbers and the fractions, so we get:
(2 - 1) + (1/2 - 2/3)
Now we can simplify this so we get:
(2 - 1) + (1/2 - 2/3)
= 1 + (3/6 - 4/6) = 1 - 1/6 = 6/6 - 1/6 = 5/6
We conclude that the difference between the mixed numbers is equal to 5/6.
If you want to learn more about mixed numbers:
brainly.com/question/1746829
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