Answer:
10×4 = 40
10^4 = 10,000
Step-by-step explanation:
10^4 is another way to write 10⁴ = 10·10·10·10 = 10,000.
Essentially, the exponent tells you how many places to the right of the leading digit the decimal point lies (here, the number of zeros in the number).
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<em>Comment on the answer choice</em>
The appropriate answer depends on what you mean by your problem statement. Some microscopes magnify 40 times; others magnify 10,000 times, so we cannot tell the appropriate answer using our knowledge of microscopes.
It's equal to 1.6x10^(-8)
we have

Solve for c--------> that means that clear variable c
so
Divide by
both sides

Adds
both sides

Multiply by
both sides
![a[(R/5)+0.3]=c](https://tex.z-dn.net/?f=a%5B%28R%2F5%29%2B0.3%5D%3Dc)
so
![c=a[(R/5)+0.3]](https://tex.z-dn.net/?f=c%3Da%5B%28R%2F5%29%2B0.3%5D)
therefore
<u>the answer is</u>
![c=a[(R/5)+0.3]](https://tex.z-dn.net/?f=c%3Da%5B%28R%2F5%29%2B0.3%5D)