Out of the following given choices;
A. theory that fish and mammals have a common ancestry
B. theory that the first organisms on Earth were heterotrophs
C. close relationship between fish and mammalian reproductive patterns
D. close relationship between humans and annelids
The answer is A. Many embryos of the kingdom Animalia share similarities in the early stages depicting that they share a common ancestor. The gill slits is one example. They diverge in later stages to become Pharyngeal in the human embryo, while they differentiate into gills in fish.
Answer:
250 years
Explanation:
The Atlantic Ocean is not static, but instead it is very active, and it is actually spreading from its central part. In its central part, this ocean has a mid-ocean ridge. This basically means that there is constant formation of new crust from the magma that comes out, and the old crust is pushed sideways as the new one is formed. On an annual level, the mid-ocean ridge is spreading out by an estimated 0.02 meters, thus that is how much the Atlantic Ocean is spreading out each year. In order to get to the result as to how many years are needed for the Atlantic Ocean to spread 500 cm, we just need to multiply the annual spreading with the number of cm in question:
0.02 x 500 =250
Thus we get a result of 250, meaning that in 250 years the Atlantic Ocean will spread out 500 cm in total.
R R Rr is the result of 1st punnet square and the genotype used to produce f2
r
r
Fossils up to 75,000 years old can be dated with Carbon-14.
Radio isotopes can be used for the age determination of the fossils. Carbon-14 is a common isotope which is used for that purpose. But the half- life of the Carbon-14 is relatively small as 5730 years. That means the amount of Carbon-14 will be half after every 5730 years. Hence, decay is very fast. So Carbon-14 cannot be used forage determination which is more than 75000 years due to the low accuracy.
Earthquake should be the answer. When tectonic plates are shifted it causes an earthquake.
