Answer:
{196, 256, 484}
Step-by-step explanation:
14² = 196;
16² = 256;
19² = 361; 390 lies between 361 and 400, and is thus NOT a perfect square;
20² = 400;
22² = 484
564 lies between the two perfect squares 23² and 24², but is itself NOT a perfect square.
Thus, the perfect squares are {196, 256, 484}