Answer:

Step-by-step explanation:
The formula of the circumference of a circle is
.
The length of an arch can be found by using the ratio of circumference to the arc.
First, find the circumference of the circle:

Then you find the ratio:
The length of the arc is 90/360, which is 1/4, of the circumference.
Finally, find the length of the arc:
or 
I hope this helps :)
<span>idk why they want the dratted "k" . it is so simple w/o it !
in the form y = ab^x, a = 4000, b = 4400/4000 = 1.1, x = t/2
N = 4000*1.1^(13/2) = 7432 <------
-----------------
now you won't be satisfied with simplicity, so
4400 = 4000e^2k
e^2k = 1.1
k = ln 1.1/2 = .0477 to 4 dp
N(13) = 4000e^(13*.0477) = 7436 <------
note that apart from a roundabout way, you get a less accurate ans !</span>
Answer:
-55
-61
064
63
Step-by-step explanation:
<span>1.d
2.c
3.b
4.d
5.b
Just took the Samples and Surveys test!
</span>
The new length of the running trail would be 6.286 miles