Originally Posted by

**ruleworld** i am trying the problem. please check if its ok or not.

Let

U, the set of all files in MyDocuments

we define the following functions

E(x), indicates if file x is encrypted

H(x), indicates if file x is hidden

Secure(x), indicates if file x is secure

Secret(x), indicates if file x contains secrets

we can now write the given statements using predicate and logical connectives

∀x ∈ U: E(x) ∨ H(x)

∀x ∈ U: E(x) ⇒Secure(x)

∀x ∈ U: Secure(x) ⇒ Secret(x)

∃x ∈ U: ¬( Secret(x) ) ⇒ ∃x ∈ U: H(x)