Answer:
D) A Survey of fellow classmates
Explanation:
This is the correct answer because an informal survey involves various answers that may or may not be accurate. Informal surveys cannot be held as scientific fact and are, therefore, not reliable. A scientific journal is reliable because it most likely includes data from an experiment and/or research of a trusted scientist or group. The results of past experiments are very reliable because these are the results of hard work and thorough planning and research. A scientific discussion with colleagues is not very credible because it involves the sharing of opinionated information, but it is certainly more reliable that the varying answers of school-aged peers.
The population of blue crabs will be difficult for the scientists to count because of unreliable ways and natural phenomenon or occurrence that causes the water's temperature to rise. According to climate reports, year 1999 have warmer temperature and this probably caused the blue crabs to be active, but on year 1990 female blue crabs sustained a normal quantity of production of their species. Thus, the estimated count of population of blue crabs is probably more accurate in year 1990 than year 1999 because of the stable production of the female crabs.
Vertebrates developed about 550 million years ago. The oldest vertebrate fossils are those of FISH with no jaws. These e<span>arly jawless fish did not have paired fins and their bodies were covered with heavy, bony scaled, but their skeletons were made of cartilage. For the next 50 million years, they were the only vertebrates.</span>
Answer:
The sperm and egg have 1/2 the amount because when the sperm fertilizes the egg, it equals out to the regular amount of chromosomes. That is why we have half chromosomes from our dad and half chromosomes from our mom, equaling out to normal amount of chromosomes.
