Which protective tissue is present in our skin?

An example of a merocrine gland is:

Ciliated columnar epithelial cells in humans are found in . . . . . . .

The inner lining of the stomach, liver, and alimentary canal is made up of which type of epithelium?

Read the following statements and answer the question.
$(i)$ It is made of a single thin layer of flattened cells with irregular boundaries.
$(ii)$ They are found in the walls of blood vessels and air sacs of lungs.
$(iii)$ They are involved in functions like forming a diffusion boundary.
Which of the following characteristics of tissue is being described by the above statements?

The inner surface of the stomach, rectum, and large intestine is lined by which type of epithelium?