Answer:
At the start of 2014, the population was growing at 8.34 million people per year.
At the start of 2015, the population was growing at 8.39 million people per year.
Step-by-step explanation:
To find how fast was the population growing at the start of 2014 and at the start of 2015 we need to take the derivative of the function with respect to t.
The derivative shows by how much the function (the population, in this case) is changing when the variable you're deriving with respect to (time) increases one unit (one year).
We know that the population, P(t), of China, in billions, can be approximated by 
To find the derivative you need to:

To find the population growing at the start of 2014 we say t = 0

To find the population growing at the start of 2015 we say t = 1

To convert billion to million you multiple by 1000

Let the required no. be x then according to question
(84/100)*x = 21
x = 21*(100/84)
x = 2100/84
x = 25
hence the required no. is 25
hope it helped
Answer:
looks like school work
Step-by-step explanation:
DO IT ON YOUR OWN
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Explanation:</h2><h2 />
The missing diagram is shown below. Remember that shapes are similar if you can turn one into the other by moving, rotating, flipping, or scaling. So this means you can make the object bigger or smaller. So in this case, we know that ΔABC is similar to ΔDEF. If so, we can establish the following proportion:

Our goal is to find x. So by Pythagorean theorem:

Conclusion:
<em>ΔABC ~ΔDEF</em>
<em>Distance across the river is 25.34m </em>