Explanation:
The perimeter of the track is the two circumferences of the semicircles (when combined, they form one circle, so we can just find the circumference of the circle) added to the lengths of the rectangle (
160
meters).
To find the circumference of the circle, we need to know the diameter.
Circumference of a circle:
d
π
or
2
r
π
, where
d
represents diameter and
r
represents radius
The diameter of the circle happens to be the same as the width of the rectangle. We know that the area of a rectangle is found by multiplying its length by its width. We know that the area is
14400
and that its length is
160
.
Width: area divided by length
14400
160
=
90
The diameter of the circle and the width of the rectangle is
90
meters.
Circumference:
90
⋅
π
=
90
π
→
If you are using an approximation such as 3.14 for
π
, multiply that by 90
Add
160
⋅
2
to the circumference since the lengths of the rectangle are also part of the perimeter.
160
⋅
2
=
320
90
π
+
320
i hope it helps you ok please mark ❣️ me as brainlist
We can solve this problem by the rule of three.
1000 protons=10³ protons
1 proton------------------2.53*10⁻³⁷g
10³ protons---------- x
x=(10³ protons * 2.53*10⁻³⁷) / 1 proton=2.53*10⁻³⁷⁺³ protons=
=2.53*10⁻³⁴ protons
answer: 2.53*10⁻³⁴ protons
You just have to divide the 1/2 a pound by 8, or equivalently multiply by (1/8):
(1/2)*(1/8) = 1/16 of a pound
I am not sure but I did this in my head and then I did it on the calculator and it was 20
