Which sets of ratios are a proportion? (Choose all that apply) * 3/11 and 17/6

12/7 and 36/21

60/55 and 7/25

7/6 and 52/48

4/10 and 8/20

Organisms that live in the alpine and taiga biomes have developed unique adaptations that aid in their survival. the douglas-fir is a conifer tree that grows in the taiga biome. it has an average height of about 70 feet, and its wood is an important source of lumber.

Find the value of x for which the lines are parallel.

Acar started driving from city a to city b, distance between which is 620 miles, at a rate of 60 mph. two hours later a truck left city b and started moving towards city a at a rate of 40 mph. how many hours after the truck's departure will the two meet?