Spotlight as a Calculator incorrect for Sin, Cos, tan, etc.

Hi,

I am a new Mac user and reading the book I have on Yosemite I was trying out Spotlight as a calculator for sin, cos, tan. To my surprise Sin 90 did not come up as 1 but I got the answer that Sin 90 = 0.89. Clearly Spotlight as a calculator is set in Rad mode and not Deg. How can I change it so that Sin 90 = 1?

B