Each half-life reduces a sample by one half.
So after 1 half-life there is 1/2 left
2 half-lives 1/4
3 half-lives 1/8
4 half-lives 1/16
5 half-lives 1/32
There would be (1/32) of 120 remaining.
or 3.75 grams.
Source:
http://www.1728.org/halflife.htm
Answer:
D
Step-by-step explanation:
X is the radius of the slice. So we must find the equation of the side of the cone.
y=mx+b, so now we must use two points to solve for the slope, or "m".
m=(y2-y1)/(x2-x1)
m=(0-15)/(5-0)
m=-15/5
m=-3 so our line so far is:
y=-3x+b, b=y-intercept=value of y when x=0, which we can see is 15 ft so:
y=-3x+15
Now the radius is x, so we must solve for x from the equation above...
-3x+15=y subtract 15 from both sides
-3x=y-15 divide both sides by -3
x=(15-y)/3
And area of this circle is:
A=πx^2, and using x found above:
A=(π/9)(15-y)^2
A=(π/9)(225-30y+y^2), so when y=6 ft
A=(π/9)(225-30*6+6^2)
A=(π/9)(81)
A=9π or if we let π=pi
A=9pi ft^2
Yes, I will help. What do you need help with?
Answer:
m=-2
Step-by-step explanation:
As the product of the roots of a quadratic equation is c/a in ax^2+bx+c=0
here a=2, b=+8, c=-m^3
Given c/a=4
-m^3/2=4
-m^3=8
m^3= -8
m=-2.