We have to calculate the height of a cylinder : h2 = ( 45 - 2 · 15 )/ 2 = 15 / 2 = 7.5 mm
Volume of the bottom of the hourglass:V = 1/3 r² π h1 + r² π h2 = = 1/3 · 6² · 3.14 · 15 + 6² · 3.14 · 7.5 = = 1/3 · 36 · 3.14 · 15 + 36 · 3.14 · 7.5 = = 565.2 + 847.8 = 1,413 mm³The rate is 10 π mm³/ sec = 31.4 mm³/secTime = 1,413 : 31.4 = 45 sec.Answer: It will take 45 seconds.
Answer:
The angle between any two faces of this pyramid is equal to 
Step-by-step explanation:
we know that
An equilateral triangle has three equal sides and three equal internal angles of measure 60 degrees
In this problem
All the faces in the regular triangular pyramid are equilateral triangles.
therefore
The angle between any two faces of this pyramid is equal to 
Answer: 
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Explanation:
We simply add the expressions we are given, though we cannot combine the terms (as they aren't like terms). There's not much to show in terms of steps, though I guess you could have the following:

Adding 4 onto 2^x means we shift the 2^x curve up four units.
Answer: 20
Step-by-step explanation: