Rule of trigonometric functions:-
sin a = cos(90 - a)
Here a = 90°.
sin 90 = cos (90 - 90)
1 = cos 0.
cos 0 = 1.
So the cos 0 = 1.
For the Fibonacci sequence you add the two previous numbers. You always start with 0, 1 and you add 0 and 1 which makes 1 then 1 + 1 makes two and so on. The next number in the sequence would be 34 + 55, meaning 89, and after that would be 55 + 89, or 144.
5.5% as a multiple is 0.055
So 700 x 0.055= $38.50 in commission
475 (standard pay) + 38.50 (commission) = $513.50 in that week