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:
-66+12 or -54
Step-by-step explanation:
To remove the parenthesis multiply the number outside of the parenthesis (in this case -6) to the numbers inside of the parenthesis (11, and -2).

A negative multiplied by a positive is a negative.

A negative multiplied by a negative is a positive.

Answer:
18.75 feet of steel pipe weighs 237 pounds
explanation:
find out how much 1 feet weighs than u can find out how much 18.75 feet.
by doing it like this
158÷ 12.5
=12.64
1 feet equals 12.64 pounds
12.64× 18.75
=237 pounds this is the answer
i do apologize if it wrong
<h3>
Answer: 4900 mph</h3>
Work Shown:
30 min = 30/60 = 0.5 hours
distance = rate*time
rate = distance/time
rate = (2450 miles)/(0.5 hours)
rate = (2450/0.5) mph
rate = 4900 mph
For the sake of comparison, a typical commercial passenger jet can reach max speeds of about 600 mph.
Answer:
1410ft²
Step-by-step explanation:
20 * 12 * 2 + [62 * (15 + 12)] =
480 + (62 * 15) =
480 + 930 =
1410ft²