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The term “public domain” refers to creative materials that are not protected by intellectual property laws such as copyright, trademark, or patent laws. ... Anyone can use a public domain work without obtaining permission, but no one can ever own it.
Answer:
The expression is :
π[cd) + π(g,h) ],[π(e,f)+π(a,b)])
We will use foreign key and primary key
Apple uses social media to promote their products and increase user-engagement. This is a very effective method of advertising.
Answer:
Here the code is given as follows,
Explanation: