get help with this essay

Example:
The supergiant star Betelgeuse has an angular diameter measured to be 0.044 arcsecond. It’s
distance is measured to be 427 light-years. What is the diameter of the star Betelgeuse?
First lets convert the measured distance to kilometers.
427 light-years  9:46  1012 kilometers
light-year
= 4:04  1015 km
and arcseconds to degrees
0:044 arcsecond
1 arcminute
60 arcseconds
1 degree
60 arcminutes
= 1:22  10??5 degrees
The equation relating distance to angle is
angular size  =
d physical size
Dseperation
360
2
solve this for the physical size to get
Physical Size d = D
2
360 = 1:22  10??5  4:04  1015 
2
360
= 8:62  108 km
0r more than 600 times the size of the sun.
Exercises:
1) There are 360 in a circle. How many arcminutes are there in a circle, arcseconds?
2) The moon has a diameter of 3500 km and an angular size of 30 arcminutes. How far away is
the moon.
3) With a measure nd the width of one of your ngers, also measure the distance from the tip
of your nose to your nger held upright at arms length. What is the angular size of your
nger?