I am listening to this woman speak. It sounds like a straight statement, not a question. There is no upward inflection at the end. Am I missing a clue somewhere that this is a question?
Not always. Sometimes the speaker does ask questions, but this time she didn't. I wasn't marked wrong but I reported it.
To me it sounded like a statement in normal speed and a question in turtle speed.
What are the meaning of "dietas"? I ask the question, because when they introduce the word, they put the image of a diet cola for "dieta".
Your diet is everything you eat, like all the different food and drinks. But it's used more often to say 'I'm on a diet' which means somebody is trying to lose weight by eating less calories or low fat fat or somehing. Also very common is the word 'diet' before the name of a soda like 'diet coke' 'diet pepsi' etc. That means that the soda is the zero calorie version.
Don't know why someone down voted you...
But yes, diet is what you eat/drink. "On a diet" means changing what you eat, usually for weight loss. If not for that purpose, there's usually an adjective, such as high-protein diet, or low-sodium diet.