<span>
The formula is </span>

<span>in the set.
This set {1,2,3} has 3 elements, so the number of subsets is gotten by
substituting 3 for the number of elements in the set:
2number of elements in the set = </span>

= 2x2x2 = 8. So there are 8 subsets. They are:
1. { } or ∅, the empty set, sometimes called the "null" set.
2. {1}
3. {2}
4. {3}
5. {1,2}
6. {1,3}
7. {2,3}
8. {1,2,3}.
Answer:
The area is changing at the point of 
Step-by-step explanation:
From the given information:
Let's recall from our previous knowledge that the formula for finding the area of a rectangle = L × w
where;
L = length and w = width of the rectangle
Suppose the Length L is twice the width w
Then L = 2w --- (1)
From The area of a rectangle
A = L × w
A = 2w × w
A = 2w²
Taking the above differentiating with respect to time

At the time t

Replacing the values back into equation 2, we get:


Answer: 3x+10y=−80
Hope this helps!