Can someone me with these problems

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?

Sara made $253 for 11 hours of work. at the same rate how much would he make for 7 hours of work?

Plzz ! if you were constructing a triangular frame, and you had wood in the length of 4 inches, 4 inches, and 7 inches, would it make a triangle? would you be able to create a frame from these pieces of wood? yes or no? = explain your mathematical thinking/show your work: