What is physical science

Physical science can be described as all of the following:

A branch of science (a systematic enterprise that builds and organizes knowledge in the form of testable explanations and predictions about the universe).

A branch of natural science – natural science is a major branch of science that tries to explain and predict nature's phenomena, based on empirical evidence. In natural science, hypotheses must be verified scientifically to be regarded as scientific theory. Validity, accuracy, and social mechanisms ensuring quality control, such as peer review and repeatability of findings, are amongst the criteria and methods used for this purpose. Natural science can be broken into two main branches: life science (for example biology) and physical science. Each of these branches, and all of their sub-branches, are referred to as natural sciences.

Source: https://en.wikipedia.org/wiki/Outline_of_physical_science

Hope this helps ma dude!  

the diploid number of chromosomes is sometimes represented by the symbol 2n. for the fruit fly, the diploid number is 8, which can be written as 2n = 8, where n represents twice the number of chromosomes in a sperm or egg cell.

the answer is "a.) well–developed vascular system."

explanation: