No, it is not. Length is a metric that is defined as the absolute value of the distance between two points.
no If the shape of the object is not fixed, it would be possible to alter the shape of the perimeter, but not the length, i.e., the distance around the object being enclosed.
it goes upside down
The answer will depend on what the shape is. That is not specified in the question and so it is not possible to give a simple answer.
First you have to define the shape in which the length is required. The length then can be established.
In order to calculate the capacity of the tank, you have to know its shape, and every dimension of that shape. For example, if it's the shape of a sphere, you need one number ... the radius of the sphere. If it's the shape of a cylinder, then you need both the radius of the end and the length of the cylinder ... two numbers. If the tank is the shape of a brick, then you need to know the length, width, and height ... three separate numbers. In your question, you haven't even told us the shape of the tank, so no answer is possible.
no If the shape of the object is not fixed, it would be possible to alter the shape of the perimeter, but not the length, i.e., the distance around the object being enclosed.
it goes upside down
a regular shape which includes many sides possible but all sides are equeal in length
Without knowing the volume of the box, it is not possible to determine the height just based on the given dimensions of length and width. You would need either the volume of the box or the 3D shape of the box to calculate the height.
There is no such shape since it is always possible to add another side.
No, a perimeter cannot be negative. The perimeter of a shape is the total length of its boundary, which is always a positive value. Perimeter is calculated by adding up the lengths of all the sides of a shape, so it cannot result in a negative value. If a calculation yields a negative number, it likely indicates an error in the measurement or calculation process.
The answer will depend on what the shape is. That is not specified in the question and so it is not possible to give a simple answer.
* no, that would mean would of your side lengh's is larger than your whole shape
First you have to define the shape in which the length is required. The length then can be established.
A circle as it has infinite number of sides
In order to calculate the capacity of the tank, you have to know its shape, and every dimension of that shape. For example, if it's the shape of a sphere, you need one number ... the radius of the sphere. If it's the shape of a cylinder, then you need both the radius of the end and the length of the cylinder ... two numbers. If the tank is the shape of a brick, then you need to know the length, width, and height ... three separate numbers. In your question, you haven't even told us the shape of the tank, so no answer is possible.
There is no limit to the number of sides that a shape can have. It is not possible to tell what the largest number is unless you know all the shapes that exist in the universe.