Monico recently hired a roofer to do some necessary work. On the final bill, Monico was charged a total of $605. The amount listed for parts was $285 and the rest of the bill was for labor. If the hourly rate for labor was $64, how many hours of labor was needed to complete the job? (A) First write an equation you can use to answer this question. Use x as your variable. The equation is

(B) Solve your equation in part (A) to find the number of labor hours needed to do the job. The number of labor hours was

For every corresponding pair of cross sections, the area of the cross section of a sphere with radius r is equal to the area of the cross section of a cylinder with radius and height 2r minus the volume of two cones, each with a radius and height of r. a cross section of the sphere is and a cross section of the cylinder minus the cones, taken parallel to the base of cylinder, is the volume of the cylinder with radius r and height 2r is and the volume of each cone with radius r and height r is 1/3 pie r^3. so the volume of the cylinder minus the two cones is therefore, the volume of the cylinder is 4/3pie r^3 by cavalieri's principle. (fill in options are: r/2- r- 2r- an annulus- a circle -1/3pier^3- 2/3pier^3- 4/3pier^3- 5/3pier^3- 2pier^3- 4pier^3)