To solve this we are going to use the formula fro the force applied to a spring:

where

is the spring constant

is the extension
Since we know the

, we can replace that in our formula and solve for

:


where

is the acceleration

is the spring constant

is the extension

is the mass
We know for our problem that

,

, and

. So lets replace those values in our formula to find

:



We can conclude that the acceleration of the block when s=0.4m is

.
Answer:
Cross price elasticity using midpoint method = 0.56
Step-by-step explanation:
Using the mid-point method
Cross-price Elasticity of Demand = <u>% change in Quantity demanded of UPS</u>
% change of price of FedEx
%change in Quantity demanded of UPS
using Mid-point method = <u> Q2-Q1 </u> × 100
(Q1+Q2)÷ 2
= <u>1.3-1.2 </u> × 100
(1.2+1.3)÷2
= <u>0.1 </u> × 100
1.25
= 8%
% change in price of FedEx
using midpoint method =<u> P2-P1 </u>× 100
(P1+P2)÷ 2
=<u> 75-65 </u>× 100
(65+75)÷2
=<u> 10 </u> × 100
70
= 14.28%
Cross-price Elasticity of Demand = 8% ÷ 14.28%
using midpoint method = 0.56
Let's use J for James's age and A for Austin's age. The equations are:
J = A - 4
3J + A² = 28
Just plug (A - 4) in the place of J in the second equation. This gives you:
3(A - 4) + A² = 28
-->
A² + 3A - 12 = 28
-->
A² + 3A - 40 = 0
-->
(A - 5)(A + 8) = 0
-->
A = 5 or -8
-8 is nonsense, so Austin is 5 years old. Therefore, James is 1 year old.
The inverse of the function is 
Explanation:
To find the inverse of the equation
, we need to interchange the variables x and y for the variables y and x.
Thus, the equation becomes

Now, we shall find the value of y.
Now, adding 8 to both sides of the equation, we have,

Interchanging the sides,

Dividing by 2 on both sides,

Taking square root on both sides,

Thus, the inverse of the function is 
The correct answer is Choice A.
If you plot the points on a graph, you will see that there is a slope of -1 and the y-intercept is (0, 3).
This matches the equation of y = -x + 3 in Choice A.