how do I calculate the power of this test ? I already found the Z value beforehand

the σ = 2

My steps are

Z= x - u/ σ

P= P(x<200 l u=196)

= P(Z<2) = 0.9772

I know that the power of a second type error 1-B= P(reject Ho l Ho true)

P(y>15 l p=0.9772) = ???

How do I calculate this ? *by the way the > in y > 15 is a > and equal sign but I do not know how to do the symbol. Thanks for reading.