**30 min of practice:**

https://www.khanacademy.org/math/geometry-home/geometry-volume-surface-area/volume-tutorial/e/solid_geometry

The goal of this exercise was to find volumes and surface areas of boxes, cylinders, and triangular prisms.

**Notes: **

The volume of a cylinder is the area of the base $×$ height.

SURFACE AREA: pi $×$

VOLUME: The areas of the top and the base are simply the area of a circle:pi $× r^2 = ? , then multiply by height$

This exercise was more difficult than expected. Finally after the 30 minutes, I was able to successfully complete the exercise and earn 475 energy points.

EXAMPLES:

**FINDING SURFACE AREA-**

radius=4 height=5

pi × r^2= pi × 4^2= 16 pi

circumference: 2(pi)(r)=2(pi) × 4=8(pi)

Surface Area: *wh*= 8(pi) × 5=40(pi)

TOTAL: 16 (pi) +16(pi)=40(pi)=72(pi)

**FINDING VOLUME-**

AREA=(pi)r^2=#(pi) × h=volume

**WORK TIME:**

So for the rest of class I found the surface area and volumes for both the cylinder and cone I created. I was having trouble at first with comprehending the formula and how to do it but then I looked at what google had to offer.

Cone:

Surface area-

A= πr(r+(square root)h^2+r^2)

Volume-

V=πr^2h/3

Cylinder:

Surface area-

A=2πrh+2πr^2

Volume-

V=πr^2h

In conclusion, in the end, when I finally got the hang of it, it was pretty easy. But I still need to practice if I am going to continue making 3d shapes.

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