A man pushes against a brick wall, which doesn't move. Is this an example of work?
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Alow cost, low earth orbit (leo) satellite is to be fabricated at a university, for subsequent launch by rocket. what are the constraints and objectives for selection of a material suitable for the satellite bus (i.e. the structure)? explain each in brief. (15 marks) b)suggest sources of data which could support the selection of materials for applications in space. (5 marks) c) set weights for the objectives listed in (2a) using the digital logic method. (5 marks)

What is the earliest point in the universe that we can observe? why can’t we see back further than this?

25pts the diagram shows the positions of the sun, moon and earth during spring tides, when the high tides are at their highest and low tides at their lowest. what is it about these positions that causes these high and low tides?