Which of the following ratios would form a proportion with 2/3?

Imagine a new pasture with grass growing on it. every day after the seeds have germinated, the number of blades of grass in the pasture triples. after 18 days, the entire pasture is completely covered in grass. how many days did it take for the pasture to be one-third covered in grass?

The inside wheels of a car traveling on a circular path are rotating half as fast as the outside wheels. the front two wheels are six feet apart. what is the number of feet in the path traced by the inside front wheel in one trip around the circle? express your answer in the form "k \pi", where k is an integer.

Create and solve a linear equation that represents the model, where squares and triangles are shown evenly balanced on a balance beam. assume the weight of a square is 1 unit and the weight of a triangle is unknown.