Question a:
Mass = Density × Volume
Density = Mass/Volume
Volume of the tree trunk (the shape of Cylinder) = Area of circular base × height
Volume = [πr²] × h
Volume = [π × 0.25²] × 20
Volume = 3.93 m³
Density = 380 kg/m³
Mass = Density × Volume
Mass = 380 × 3.93
Mass = 1493.4 kg
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Question b)
The growth ring = 4 millimeters = 4÷1000 = 0.004
New diameter = 0.5 + 0.004 = 0.5004
New height = 20 + 0.2 = 20.2
New volume = [πr²] × h
New volume = [π × 0.2502²] × 20.2
New volume = 3.97 m³
<span>its C. Alan has 13 CDs, Tom has 16 CDs, Barbara has 23 CDs !</span>
Just took this test on k12. The answer is 260cm. Hope this helps!!
