If she spent $42.15 on dinner it does not matter that this is half.
The equation should be: x-42.15

20
I hope that this is the answer that you are looking for.
I shall name every “thing” here on this planet Sam
Answer:
A. A marine biologist measures the lengths of the dorsal fins of a number of tiger shark: In this case, the biologist needs to sample the sharks, make measurements and organize in tables the data obtained from the two variables measured in each of the analyzed individuals.
C.An ornithologist, a scientist who studies birds, draws a sketch showing the colors of a bird’s plumage.
in this case the ornithologist had to make observations of birds of different species and through schemes report and organize according to the species what color of plumage they have.
D.An ecologist uses a computer to make a graph of the measurements of the rings of a tree:
The graph is the way in which the scientist systematizes the data for the analysis of the tree rings. these trees had to be sampled
Explanation:
Spermatogenesis is the process by which haploid spermatozoa develop from germ cells in the seminiferous tubules of the testis. ... The spermatids are transformed into spermatozoa (sperm) by the process of spermiogenesis. These develop into mature spermatozoa, also known as sperm cells.