My table that was created ->
create table newempchart_cg1308
(firstname varchar(15),
lastname varchar(20),
title varchar(15),
age number(3),
salary number (6,2));

I have tried all 3 of these to "insert" values into a table:

insert into newempchart_cg1308
(firstname, lastname, title, age, salary)
values ('Jonie', 'Weber', ‘Secretary’, 28, 19500.00);
('Potsy', 'Weber', ‘Programmer’, 32, 45300.00);
('Dirk', 'Smith', ‘Programmer II’, 45, 75020.00);

insert into newempchart_cg1308
(firstname, lastname, title, age, salary)
values ('Jonie', 'Weber', ‘Secretary’, 28, 19500.00);
values ('Potsy', 'Weber', ‘Programmer’, 32, 45300.00);
values ('Dirk', 'Smith', ‘Programmer II’, 45, 75020.00);


insert into newempchart_cg1308
(firstname, lastname, title, age, salary)
values ('Jonie', 'Weber', ‘Secretary’, 28, 19500.00);
insert into newempchart_cg1308
(firstname, lastname, title, age, salary)
values ('Potsy', 'Weber', ‘Programmer’, 32, 45300.00);
insert into newempchart_cg1308
(firstname, lastname, title, age, salary)
values ('Dirk', 'Smith', ‘Programmer II’, 45, 75020.00);

It always says: Invalid characters used in command.

The sample was->
insert into employee
(first, last, age, address, city, state)
values ('Luke', 'Duke', 45, '2130 Boars Nest', 'Hazard Co', 'Georgia');

What am I doing wrong?