Given two stars with angles of declination and right ascension (d 1 , a 1 ) and (d 2 , a 2 ), the angle they subtend is given by the formula where a 1 and a 2 are angles between -180 and 180 degrees,...

Given two stars with angles of declination and right ascension (d₁, a₁) and (d₂, a₂), the angle they subtend is given by the formula

where a₁
and a₂
are angles between -180 and 180 degrees, d₁
and d₂
are angles between -90 and 90 degrees, a = a₂
- a₁, and d = d₂
- d₁. Write a program to take the declination and right ascension of two stars as command-line arguments and print the angle they subtend. Hint: Be careful about converting from degrees to radians.