> ${Occupation}(p,o)$: Predicate. Person $p$ has occupation $o$. > ${Customer}(p1,p2)$: Predicate. Person $p1$ is a customer of person $p2$. > ${Boss}(p1,p2)$: Predicate. Person $p1$ is a boss of person $p2$. > ${Doctor}$, $ {Surgeon}$, $ {Lawyer}$, $ {Actor}$: Constants denoting occupations. > ${Emily}$, $ {Joe}$: Constants denoting people. Use these symbols to write the following assertions in first-order logic:

1. Emily is either a surgeon or a lawyer.

2. Joe is an actor, but he also holds another job.

3. All surgeons are doctors.

4. Joe does not have a lawyer (i.e., is not a customer of any lawyer).

5. Emily has a boss who is a lawyer.

6. There exists a lawyer all of whose customers are doctors.

7. Every surgeon has a lawyer.

Consider a vocabulary with the following symbols:

> ${Occupation}(p,o)$: Predicate. Person $p$ has occupation $o$.
> ${Customer}(p1,p2)$: Predicate. Person $p1$ is a customer of person $p2$.
> ${Boss}(p1,p2)$: Predicate. Person $p1$ is a boss of person $p2$.
> ${Doctor}$, $ {Surgeon}$, $ {Lawyer}$, $ {Actor}$: Constants denoting occupations.
> ${Emily}$, $ {Joe}$: Constants denoting people.
Use these symbols to write the following assertions in first-order
logic:

1. Emily is either a surgeon or a lawyer.

2. Joe is an actor, but he also holds another job.

3. All surgeons are doctors.

4. Joe does not have a lawyer (i.e., is not a customer of any lawyer).

5. Emily has a boss who is a lawyer.

6. There exists a lawyer all of whose customers are doctors.

7. Every surgeon has a lawyer.