Answer: 
Step-by-step explanation:
Given
Population of dust particle doubles every 30 minutes
If the initial sample is 21 grams
The model to predict the population will be

Where t=time in hours
A day has 24 hours . So, for 2 days time is 48 hours
Population is given by
Answer:
10.2π
Step-by-step explanation:
Given data
Area of circle= 81 ft^2
Also, the expression for the area of a circle is
A=πr^2
substitute
81=3.142*r^2
r^2= 81/3.142
r^2= 25.77
square both sides
r= √25.77
r= 5.1
Also, the expression for the circumference is
C= 2πr
substitute
C= 2*π*5.1
C= 10.2π
Hence the circumference is 10.2π
To solve part a, do the following.
49.84-44.50=<span>5.34
5.34/44.50=x/100
after solving the proportion, x would be equal to 12.
To solve part b, do the following.
50+12=62
</span>To solve part c, do the following.
The amount of the tip is:
x/<span>57.50=62/100
which is </span><span>35.65
The total bill is:
35.65+</span>57.50=<span>93.15</span>
Im pretty sure it is length times width :)
Answer:
D is the correct answer
Step-by-step explanation:
Not all rectangles are squares.