A programming language is not used to talk from human to human. It is used to talk from a human to a computer. Computers are very dumb compared to us, so they need to be taught or spoken to in simple terms. Asking them something complex is far beyond their understanding, as they cannot learn anything beyond what has already been taught to them. Using print: “Hello, World” is the way to tell them to do stuff way less complex than when we say ‘write the words Hello, World on the screen’. A programming language is also not very easy to create. Talking to a computer in a dumb way reduces the process to make a new language for the computer to understand.
Yes Microsoft and Apple used the closed-source approach to better secure from malware and make to make their operating systems more user friendly.
Answer:
a) We know that atleast one or more author writes a book.
Symbol to indicate one or more is (B)
So the correct option is B
b) We know that zero to multiple books are written by any author.
Symbol to indicate zero or more is (A)
So the correct option is A
c) The fourth option is correct if we replace by many to many relationship and generate a new entity.
So the relationship betweem author and contract is one to many. So we know that there is atleast one author that represent in symbol d and books has atleast 0 that represent in symbol c.
So Fourth Option is correct d at blue side and c at red side.
d) There are two forirgn keys in table Contract one is from AuthorId and other is ISBN.
So correcct option is C
