First and third, second can still be simplified.
Answer:
C. (3, 3)
Step-by-step explanation:
It would be 40•.25=10 which means 40-10=30 so it’d be .25 and you’d move the decimal over 2 spots so it’d be 25% off
D. 3 and 9
(Also 12 which isn’t in the options)
3:1,3
9:1,3,9
12:1,2,3,4,6,12