Your new slogan is copyrightable - wrong -

• Short slogans are not considered to embody sufficient authorship for copyright protection.

• If, however, the slogan is used as a trademark, protection might be available under the trademark laws.  See slogans, about trademarks.

Copyright is an inexpensive way to protect your invention - wrong -

• Publish and the invention will become public domain property.

• Copyright is not a "poor man's patent" no matter who claims it is.

• Copyright does not protect the ideas or techniques or information.  more

Avoid infringement by changing five features - probably wrong -

• The test will be similarity between yours and theirs.

• If the key features remain in yours, which they often do, copyright infringement has not been avoided.

You purchased an original painting and now you own the copyrights - wrong -

• The purchase of an original art object does not pass on the author's copyrights thereto.

• Copyrights can, however, be transferred by contract.