1.001 is greater than 0.111 because the 1 is automatically greater than zero. 1.11 is greater than 1.01 because there is a place in the tenths place in 1.11 but none for 1.01.
The answer to the question
Cosine(angle) = adjacent leg/ hypotenuse
Cosine( angle ) = 18/20
Angle = arccos(18/20)
Angle = 26 degrees
Every other number from the first, 3rd, 5th, ..etc it adds 2 for the next number.
For the 2nd, 4th, 6th, etc term, its supposed to be 90, 78, 65, 51?
If so, It started with -12 then -13 after that -14 find the next term, all you need to do is to -15 to the current number, which is 51. then you get 36