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:
Sorry I can't answer this.
But you may use the protacter to find the angle
Please note that pi has just one value. The only difference stems from round-off error when you don't use all of the digits following "3.14159 ... " to represent the value of pi. The formula for circumference is C = 2 pi r, or C = pi d,
where r=radius and d=diameter.
Circle A: Diameter 9 inches and Circumference of 28.26 inches
If the diameter is 9 inches, then C = 28.26 inches = pi (9 inches). Divide 28.26 inches by 9 inches. Note that you MUST round off the ratio (pi) that you obtain, since 28.26 has 4 significant figures and 9 has just one.
28.26
------- = 3.14, but because 9 has just one significant figure, you must round
9 this 3.14 to just 3.
No, because she will go over by .57 cents. So she won't be able to buy the gift. You can find the answer by dividing 18 by 7 and adding that answer to 18 to get the amount total you owe including tax.
C. 84
12 x 8 is the area of the whole thing but you subtract 12 because of the missing 6x2 part of the square