Since, the options have not been given the question is incomplete.
What is Darwin's name for species that do not appear to have changed for millions of years?
a.
Dinosaurs
b.
Living fossils
c.
Old souls
d.
Ancient moderns
Answer: b. Living fossil
Explanation:
In 1859 Charles Darwin proposed the term living fossil, that means a species or group of species that had not changed in terms of evolutionary context thus can be useful in tracing the extinct or previously existing forms of life. The examples of the living fossils are horseshoe crabs, ginkgo (Conifers) and tuatara. These group of animals were existed unchanged in the Ordovician, Permian, and Triassic periods respectively with few surviving species.
Answer:
Object 4 in the example
Explanation:
For simplicity and a clearer view of this problem, let's assume that four masses from 1 to 4 have the the masses 2 kg, 4 kg, 6 kg, 8 kg respectively.
According to the second Newton's law, we know that force is directly proportional to both mass and acceleration. The equation representing this is
.
Notice that all of them have the same acceleration. This means, the greater the mass, the greater the force for a fixed acceleration. Simply speaking, the forces for each of the objects would be 2a, 4a, 6a and 8a respectively.
Since we're interested in the magnitude of the force and not direction, we neglect whether acceleration is positive or negative. This means that object 4 will require the greatest force to move, as it has the greatest mass.
In this case a double displacement reaction will take place.
They are all things you can do to elements on the periodic table?