Answer:
B. pre-zygotic, lock and key
Explanation:
When pollens from the different species fall on the stigma of a flower from some other species, the chemicals released from the stigma do not allow the pollens to germinate. The pollen tube is not formed to carry the male gametes to the egg cell for fertilization. Since this process does not allow the formation of zygote between the male and female gamete of two different species, it is a pre-zygotic isolating mechanism.
Here, the pollens and stigma of different plant species are not compatible with each other and the structural incompatibility of the reproductive structures prevents fertilization. This represents the lock and key mechanism of reproductive isolation.
<span>B. Marsupials. </span>Amniotic eggs is a unique kind of egg because they possess a semipermeable shell to protect the egg but it also allows gas exchange. Inside an amniotic egg contains the amnion, chorion and allantois. Animals that lay amniotic eggs are called amniotes, which include reptiles, birds, dinosaurs, monotremes (platypus).
Deep water has <span>a wavelength of two meters forms in water with a depth of twenty meters.</span>
The original six frigates of the United States Navy<span> came up with the Naval Act of 1794. Two<span> characteristics are distinct of these said early US. Navy "super frigates. They are: </span></span>
<span>· </span><span>timbers put close together to be able to withstand heavy cannon fire</span>
<span>· </span><span>hull reinforced to resist the pressures of heavier ordnance on deck</span>
Answer: The program completed in a quarter of the time with four computers versus one computer
Explanation:
Distributed computing simply means using distributed systems in solving computational problems and this is done as the problem is divided into many tasks, whereby the tasks are accomplished by one or more computers.
Following the information given in the question, a speedup of 4 indicate that the program completed in a quarter of the time with four computers versus one computer.
