Answer:
Radius length: √5
Standard Form (Equation): (x + 4)^2 + y^2 = 5
Step-by-step explanation:
First we will determine the radius;
Center: (-4, 0)
Point on Circumference: (-2, 1)
d = √(-2 - (-4))^2 + (1 - 0)^2 = √(2)^2 + (1)^2
= √4 + 1 = √5
Therefore the radius is of length √5
Now the equation of a circle is in the form ((x - h)^2 + (y - k)^2) = r^2. The center is in the form (h,k) and r is the radius. Given this our equation would be (x - (-4))^2 + (y - 0)^2 = (√5)^2, or [simplified] (x + 4)^2 + y^2 = 5.
1hr 6min left because all you have to do is keep subtracting
After 1 hour, 360 g decays to 180 g.
After another hour (total 2 hours), 180 g decays to 90 g.
After another hour (total 3), 90 g decays to 45 g.
After one more (total 4), 45 g decays to 22.5 g.
More quickly, with a half-life of 1 hour, the 360 g of starting material decays to
(360 g) / 2⁴ = 22.5 g
In general, if the half-life is 1 hour, then after <em>n</em> hours, an initial amount <em>A</em> of this substance decays according to
<em>A</em> / 2<em>ⁿ</em>
Answer:
0.74 to 6.06
Step-by-step explanation:
The groups are independnet,
SE(xh bar-xa bar)=sqrt [sh^2/nh+sa^2/na]=sqrt [10.1^2/80+10.3^2/80]=1.61
At df=157, the t critical is 1.65
90%c.i=(xh bar-xa bar)+-tcritical SE(xh bar-xa bar)
=(25.2-21.8)+-1.65*1.61
=0.74 to 6.06
