To start, the question is asking for surface area of a cylinder, meaning you will have to use this formula to find it: A=2πrh+2πr^2.
Since you already know that the diameter of the plastic cylinder is 4 marbles long, and each marble is 2 cm in diameter, you would multiply 4 and 2 to get that your diameter is 8 cm. However, since the surface area of a cylinder formula uses radius, you would simply divide 8 by 2 to get that the radius of the cylinder is 4 cm.
Now, since you already know that the height of the cylinder is equal to 10 marbles, multiply the amount of marbles by 2 to get that the height of the cylinder is 20 cm.
Now that you know the height and the diameter of the cylinder, plug the values into the formula: A=2π(4)(20)+2π(4)^2.
Assuming that pi is 3.14, simplify the equation as according to PEMDAS and you get that the area of plastic needed to make one cylinder is 602.88 cm squared
Rounding Average because finding an average is the most efficient way to find the answer of this question
In order to find the slope of a line, u must use the slope formula. Which is (y2-y1/x2-x1). For example if you had a set of coordinates that are (6,4) and (2,8) you would first sub the 8 from4 which gives you 4. The u do the same with 2 and 6 which gives u 4. After that you divide 4 by 4. and your answer is 1
Http://chestofbooks.com/architecture/Building-Construction-V2/images/Stone-Steps-173.jpg
There ya go