Answer:
3) 16.2
Step-by-step explanation:
The supplement to the 115° angle on the right is 65°, the same as the angle at upper left. The vertical angles at C are the same measure, so this tells you that the two triangles FCB and ACD are similar by the AA similarity postulate. That being the case, corresponding sides are proportional:
CB/CD = CF/CA
CB = CD·CF/CA = 7.2·21.6/9.6
CB = 16.2
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When given two "point-to-point" triangles like this, quite often there is some sort of similarity relationship involved. First, you need to figure out what it is; then you need to make use of it as needed to answer the question being asked.
ANSWER
The volume of the mailing tube is 678.6 square inches to the nearest tenth.
EXPLANATION
The volume of a cylinder is calculated using the formula;

Since the mailing tube is in the form of a cylinder, we use this formula to find its volume.
We substitute h=24 and r=3 to obtain,



The answer is 515. Because 5×103 is 515