Step-by-step explanation:
Arc length formula is

where x is radinas.
A semi circle has a radian measure of

The radius is half of the diameter, 12 so the radius is

So the arc length is

Area of semi circle is

where r is the radius.



Answer:
B
Step-by-step explanation:
I took the test
Answer:

Step-by-step explanation:
Given expression:

Rewrite 32 as 16 · 2:

Apply radical rule 

As
:

Multiply by the conjugate:



As
:




Answer:
The rate at which the distance from the plane to the station is increasing when it is 2 mi away from the station is 372 mi/h.
Step-by-step explanation:
Given information:
A plane flying horizontally at an altitude of "1" mi and a speed of "430" mi/h passes directly over a radar station.


We need to find the rate at which the distance from the plane to the station is increasing when it is 2 mi away from the station.

According to Pythagoras


.... (1)
Put z=1 and y=2, to find the value of x.




Taking square root both sides.

Differentiate equation (1) with respect to t.

Divide both sides by 2.

Put
, y=2,
in the above equation.

Divide both sides by 2.



Therefore the rate at which the distance from the plane to the station is increasing when it is 2 mi away from the station is 372 mi/h.
You multiply 2 by 0.085 and you get the answer
$0.17
Then add $0.17 and $2 and you get $2.17