Answer:
im late but if anyone sees this question its 0.9423
Explanation:
The test predicting that he does not have the drug and is correct is 0.98 x 0.25.
Predicting that he does not have the drug but is wrong is 0.02 x 0.75

Got a 5/5 on plato. The other similar answer is 0.245 for the shorter question