Which ratios form a proportion?

a. 4/9 , 12/25
b.3/7, 18/42
c. 5/11, 20/45
d.5/8, 15/25

The marked price of an article is 25% above its selling price and the cost price is 30% less than its marked price . find the discount percent and gain percent. only a brainlest can solve it i will mark you brainlest

What is the area of a triangle with vertices at (-3 3) (-3,2) and (1,2)?

Find the distance between (7,-6) and (-3,-9)