The answer should be D.
Hope it helped you.
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
Answer:
The unit ratio would be 8 grams per milliliters
Step-by-step explanation:
Since, the unit ratio is a fraction with denominator 1,
In other words, the amount of one quantity in unit amount of other quantity is called unit rate or unit ratio.
Here, the amount first quantity = 16 grams,
The amount of second quantity = 2 milliliters,
Thus, unit ratio = 
= 8 grams per milliliters
20 and 45x
We look for a number that can go into both numbers.
5 into 20 is 4 and 5 into 45x is 9x.
5: 20 45x
4 9x
So no other number can go into 4 and 9x again.
So the GCF of 20 and 45x is 5.
Hope this explains it.