ini bagaimana caranya tolong jawab

1. a. A= {x| 2, 3, 5, 7, 11, 13, 17, 19 , x < 20}
b. B= {x| 1, 2,3,4,5,6,7,8,9,10,12}
c. C={x| 1,4,9,16,25,36,49,64,81}
d. D={x| 1,2,3,4,5,6,7,8,9 , x < 10 }