Answer:
There will be less than 1 gram of the radioactive substance remaining by the elapsing of 118 days
Step-by-step explanation:
The given parameters are;
The half life of the radioactive substance = 45 days
The mass of the substance initially present = 6.2 grams
The expression for evaluating the half life is given as follows;
Where;
N(t) = The amount of the substance left after a given time period = 1 gram
N₀ = The initial amount of the radioactive substance = 6.2 grams
= The half life of the radioactive substance = 45 days
Substituting the values gives;
The time that it takes for the mass of the radioactive substance to remain 1 g ≈ 118.45 days
Therefore, there will be less than 1 gram of the radioactive substance remaining by the elapsing of 118 days.
Answer:
y=-⅗x+3
Step-by-step explanation:
5y=-3x+15. Divide 5 on both sides
5. 5
y=-⅗x+15/5
y=-⅗x+3
Hope this helps :)
Answer:
<h2>√512 by √512 </h2>
Step-by-step explanation:
Length the length and breadth of the rectangle be x and y.
Area of the rectangle A = Length * breadth
Perimeter P = 2(Length + Breadth)
A = xy and P = 2(x+y)
If the area of the rectangle is 512m², then 512 = xy
x = 512/y
Substituting x = 512/y into the formula for calculating the perimeter;
P = 2(512/y + y)
P = 1024/y + 2y
To get the value of y, we will set dP/dy to zero and solve.
dP/dy = -1024y⁻² + 2
-1024y⁻² + 2 = 0
-1024y⁻² = -2
512y⁻² = 1
y⁻² = 1/512
1/y² = 1/512
y² = 512
y = √512 m
On testing for minimum, we must know that the perimeter is at the minimum when y = √512
From xy = 512
x(√512) = 512
x = 512/√512
On rationalizing, x = 512/√512 * √512 /√512
x = 512√512 /512
x = √512 m
Hence, the dimensions of a rectangle is √512 m by √512 m
Answer:
last one
Step-by-step explanation:
You are swinging A(-1,-2) around the center which in this case is the origin. Keep in mind that points on a circle all have a equal distance from the origin. We don't want the distance from the center to change.
We want the center of that circle to be the origin.
So the answer is the last one:
"Create a circle with the origin as its center and a radius of the origin and point A, then locate a point on the circle that is 90° counterclockwise from point A. "
Step-by-step explanation:
let the blank be x
therefore,
