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
There is no such shape since it is always possible to add another side.
* no, that would mean would of your side lengh's is larger than your whole shape
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.
A circle as it has infinite number of sides
Answer not possible to get area from one length measurement unless given the shape of this length. For example if the shape is a square of perimeter 27 cm. then the side length is 27/4 and the area is (27/4) x (27/4) square cm.
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.
The radius can't be negative. The shape would simply not exist.