Brian is participating in a 4-day cross-country biking challenge. He biked for 48, 55, and 58 miles on the first three days. How many miles does he need to bike on the last day so that his average (mean) is 54 miles per day?

Ijust need to see how to do this. so you don’t have to answer all of them just a step by step explanation of one.

If you prove that ∆wxz is congruent to ∆yzx, which general statement best describes what you have proved?

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)