Answer:
The values reported by Uma, Salina, and Tamara are all possible values for inverse cosine 
Step-by-step explanation:
Solution:-
- The solution to the inverse "cosine" problem would have a general form:
                                     θ = cos^-1 ( a )
Where,  a: Any arbitrary constant, - 1 < a < 1
- The value of θ = 52° was reported by Salina suggests that the answer lies in the first quadrant of a cartesian plane where ( sin (θ) , cos (θ) , tan (θ) ) have positive values for "a". 
Hence,                            0 < a < 1 , θ = 52°
- The value of θ = 128° was reported by Tamara suggests that the answer lies in the second quadrant of a cartesian plane where ( sin (θ) ) have positive values for "a" and (cos (θ) , tan (θ) have negative values for "a". So for cos (128):
Hence,                           -1 < a < 0 , θ = 128°
- The value of θ = 308° was reported by Uma suggests that the answer lies in the fourth quadrant of a cartesian plane where ( cos (θ) ) have positive values for "a" and (sin (θ) , tan (θ) have negative values for "a". So for cos (308):
Hence,                           0 < a < 1 , θ = 308°
- The angle θ reported by Uma and Salina are similar solution because of property law of complementary angles:
                                      cos (θ) = cos ( 360 - θ )
Where, θ = 52°,            cos (52°) = cos( 308°)  .. Uma and Salina conform
However,                      cos ( 180 - θ ) = - cos (θ)  
                                      cos(128) = - cos ( 52 ) .... Uma and Tamara conform.