This is true I looked up in the science dictionary.
Answer:
Magnification can be calculated using a scale bar. ... Magnification = scale bar image divided by actual scale bar length (written on the scale bar).
Answer: d. Extracellular matrix was discovered more than 20 years ago.
Explanation:
According to biological sciences, the extracellular matrix is a matrix that consists of three dimensional network of extracellular macromolecules such as enzymes, collagen and glycoproteins which provide structural and biological support for surrounding cells as well.
It is found that it is discovered over 20 years ago in the matrix formed in the mouse EHS sarcoma. Therefore, correct answer is (d).
The right answer for the question that is being asked and shown above is that:
The density of a certain object can be solved using two parameters: The mass and the volume.
Density = mass / volume.
So, from the given question, we are lacking on what the volume is.