true ?

Question

Which of the following statement(s) is/are true?
I.Every existence dependency results in a weak entity.
II.Role names are technically not necessary in relationships types when all the participating entity types are distinct.
III.The relationship between owner entity and the weak entity is one to many.

Answer 1

if existence dependency is there means entity does not exist without an owner so it should be weak entity hence 1st seems to be true

2nd is also true

3rd may or may not be true

Comments

I doubt 1st one

3rd is True

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1st statement is false 

https://books.google.co.in/books?id=v_j0CSS3m7MC&pg=PA77&lpg=PA77&dq=Every+existence+dependency+results+in+a+weak+entity.&source=bl&ots=6n9PsbEJub&sig=4KHaT1zfRdekDqTPMhmQ0wAFuww&hl=en&sa=X&ved=0ahUKEwihyY3vhKXQAhVGuo8KHTN0CggQ6AEIOjAF#v=onepage&q=Every%20existence%20dependency%20results%20in%20a%20weak%20entity.&f=false page 77

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consider STUDENT relation (sid,rollno).

every student is having unique roll number.

so dependency exist between sid and rollno.it may be sid->rollno.but it is not weakentity ,it is strong entity set.

for universal quantifier($\forall$ )if one case is false entire set is false.

so it is not true