Doubt yourself, and you doubt everything you see. Judge yourself and you see judges everywhere. But if you listen to the sound of your own voice, you can rise above doubt and judgement, and you can see forever.
 - Nancy Kerrigan

Grade 8

Theory: 

 Surface Area of Rectangular Prisms

A rectangular prism has 2 ends and 4 sides. Opposite sides have the same area. The surface area is the sum of the areas of all six sides.

How to find the surface area of Rectangular Prisms:

Find the area of two sides (Length Height) 2 sides

Find the area of adjacent sides (Width Height) 2 sides

Find the area of ends (Length Width) 2 ends

Add the three areas together to find the surface area

Example: The surface area of a rectangular prism 5 cm long, 3 cm. wide and 2 cm. high = 5 2 2 + 3 2 2 + 5 3 2 = 20 + 12 + 30 = 62 cm².

Solutions from the Previous Issue:

Calculate:

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Proposed Exercises:

Find the volumes of spheres having the following radii:

1.        40 cm

2.        60 cm

3.        12 cm

4.        4 cm

Find the volume of spheres having the following diameters:

5.        25 cm