B = (uNI)/L, or in words, The magnetic field(B) equals the magnetic constant(u) times the number of turns(N)times the current(I) divided by the length of the solenoid(L)

B = 3.2 x 10^-3 T
u = 4pi x 10^-7
N = ?
I = 5A
L = 2.06m

B = (uNI)/L
BL = uNI
(BL)/(uI) = N

3.2 x 10^-3 T x 2.06 m / (4pi x 10^-7 x 5 A) = approximately 1050 turns

I'm not super sure this is it, since I don't remember the exact formula, so I looked it up on wikipedia.
But 1050 turns over 2.06 turns sounds somewhat reasonable.

Highest grade in my AP Physics class and recipient of the physics departmental award at my high school

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