1. Find the surface area of the rectangular prism. (1 point) <span>Measures are 2, 3, and 4 inches. Let W=2, L=3, H=4 </span> <span>a rectangular has six sides, the total surface area is equal to 6 plains: </span> <span>2*W*L + 2*L*H + 2*L*W </span> <span>= 2*(W*L + L*H + L*W) </span> <span>= 2 * (2*3 + 3*4 + 4*2) </span> <span>= 2 * ( 6 + 12 + 8 ) </span> <span>= 2 * 26 </span> <span>= 52 ................... the last choice </span>
<span>2. A cube has a side length of x feet. Which expression represents the surface area of the cube? (1 point) </span>
<span>Area of one face = x^2, Total Area of 6 faces = 6*x^2 = 2x^2 units </span>
<span>3. Find the surface area of the cylinder. Use 3.14 for pi . (1 point) </span> <span>Length: 15 cm, Diameter: 2 cm </span> <span>A cylinder has 3 surfaces: two circles + one curved surface area </span> <span>...... two circles of 2cm diameter (1cm radius) </span> <span>A = pi*r^2 = 3.14*1*1 = 3.14 sq. cm ...... two circles' area = 6.28 sq.cm </span> <span>Curved surface area = circumference * length </span> <span>.... circumference = pi*d = 3.14 * 2 = 6.28 cm ......... length = 15 </span> <span>curved surface area = 6.28*15 = 94.2 sq. cm </span>
<span>Add both for total surface area = 6.28 + 94.2 = 100.48 sq.cm </span>
<span>4. The bottom of a shopping bag measures 8 inches by 10 inches. The bag has a height of 12 inches. How much paper is needed to make the bag? (1 point) </span> <span>two pieces of paper ... one for bottom = 8*10 = 80 sq.in </span> <span>the other ... height * perimeter of the bottom = 12*(2*(10+8)) = 12 * 2 * 18 = 432 sq.in </span> <span>Add both: 80 + 432 = 512 sq.in <<<<<<<<<<<</span>
