I need some help in this question

M∠abc=138° and m∠def=31° . which statement is true about ∠abc and ∠def ? a: the angles are neither complementary nor supplementary. b: the angles are complementary. c: the angles are supplementary.

Find two numbers if their ratio is 4: 7 and their difference is 123.

The sum of 15 and two times a number is 29 . what is the number