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why is the Harvard architecture is sometimes used in preference to the von Neumann architecture and give examples of each system

The Harvard architecture can fetch instructions while accessing data memory at the same time.The Harvard architecture is used for embedded computers and von Neumann architecture is used for desktops.

Answered by • Computing tutor

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Explain why the first ionisation energy of Al is less than that of Mg?

The outer electron on aluminium is removed from the 3p sub-level, whereas the outer electron on magnesium is removed from the 3s sub-level.The 3p sub-level is higher in energy than the 3s sub-level.Alumin...

Answered by • Chemistry tutor

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Describe how you would use a biochemical test to show that a solution contained a protein (2 marks)

Biuret testThe solution colour changes to: Lilac / purple / mauve / violet(specific colour required, reject blue or pink)

Answered by • Biology tutor

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Name two enzymes involved in DNA replication (2 marks)

DNA helicase (1 marks)DNA polymerase (1 marks)

Answered by • Biology tutor

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Which of the following was of greater importance as a reason for overseas exploration, 1445-1570? (i) Religion (ii) Technological change

Religion was undoubtedly a vital motivating factor for overseas exploration in Spain and Portugal. Within the Reconquista, ending for Portugal with the capture of Farzo in 1249 and for Spain with the conq...

Answered by Abigail C. • History tutor

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