Name the university and country which had the highest number of international students in 2015.
highest number of international students refers to MAX(DIVIDE(MULTIPLY(num_students, pct_international_students), 100)); in 2015 refers to year = 2015; name of university refers to university_name;
SELECT T1.university_name, T3.country_name FROM university AS T1 INNER JOIN university_year AS T2 ON T1.id = T2.university_id INNER JOIN country AS T3 ON T3.id = T1.country_id WHERE T2.year = 2015 ORDER BY T2.num_students DESC LIMIT 1