<PRE><B>Question 1205446</B>
&lt;br&gt;
Outside diameter 12cm&lt;br&gt;
Outside radius 12/2 = 6cm&lt;br&gt;
Thickness = 4mm = 0.4cm&lt;br&gt;
Inside radius 6-0.4 = 5.6cmm&lt;br&gt;
Volume of metal: {{{(4/3)(pi)(6^3-5.6^3)}}}&lt;br&gt;
The mass is the volume of metal, multiplied by the density of the metal.&lt;br&gt;
I leave the calculations to the student.&lt;br&gt;
(ANSWER: 1488.6g, to one decimal place)&lt;br&gt;
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