Svetlana, this is the same as your question about Mon adresse. The noun starts with a vowel so it is cet etudiante, even though the student is female. Use cet when the noun begins with a vowel.

Yes, it's clear now. Thanks a lot!

Sorry for the bad formatting, it's quite hard to read that way but all the new lines were removed... .

Actually there are 4 adjectives like this : ce, cet, cette, ces - "cette" for every feminine noun, no exception : cette voiture, cette étudiante - "ce" for masculine noun starting with a consomn : ce chien, ce crayon, ce lit - "cet" when the masculine noun starts with a vowel (like it's written in your textbook): cet oiseau, cet avion - "ces" is the plural form and is for all genders: ces voitures, ces étudiantes, ces étudiants, ces chiens, ces avions, ... I hope that's more clear for you !

Thank you for comments. My textbook gives the rule that before words starting with a vowel (words of either feminine or masculine gender) goes 'cet'. But I cannot find a rule like this on the internet.