9. Emma is choosing new tile for the floor in his dining room, which is in the shape of a square with side length x feet. The tile costs $3.39 per square foot.

a. Write the function f for the cost of the flooring.

b. Determine the cost of the flooring if she decides on a dining room with side
lengths of 11 ft.

c. Determine the cost of the flooring if she decides on a dining room with side
lengths of 23 ft.

The graph of y = ax^2 + bx + c is a parabola that opens up and has a vertex at (0, 5). what is the solution set of the related equation 0 = ax%2 + bx + c?

Savannah is painting a striped background for a mural on a wall that is 1515 yards long. she wants a total of 9696 stripes that are all the same width. which calculation should savannah use to decide how wide to make each stripe?

Afactory makes propeller drive shafts for ships. a quality assurance engineer at the factory needs to estimate the true mean length of the shafts. she randomly selects four drive shafts made at the factory, measures their lengths, and finds their sample mean to be 1000 mm. the lengths are known to follow a normal distribution whose standard deviation is 2 mm. calculate a 95% confidence interval for the true mean length of the shafts. input your answers for the margin of error, lower bound, and upper bound.