Write the Word or Phrase That Best Completes Each Statement $5 \times 3$

Short Answer

Write the word or phrase that best completes each statement or answers the question.
Provide the missing information.
-If A is a $5 \times 3$ 3 matrix and B is a $3 \times 7$ trix, then the product AB will be a matrix of order________. The product BA (is/is not) defined.