How hard is it to break a Google Form?

Question

Burglary protection

At first I wanted to ask: "Is it possible to break a Google Form?", but then I realized that everything can be broken, if there is a desire. =)
The situation is the following.
A Google Form is used to submit responses to a game that has cash prizes. The amount of winnings depends on the correctness and speed of the entered answers.
Accordingly, to check the correctness of the answers, the standard functionality of the forms is used.
With the development of the game, the amount of winnings also increases. In this regard, the question is brewing that sooner or later the moment may come when players will use dishonest methods to win: brute force the correct answers, ddo the form itself so that other players cannot answer, try to snatch the correct answer from the form (after all, with what - then the player's answer is compared) ...
Here is the question. Up to what point no one will bother with this, and after what - there may be no honest players left? What are the vulnerabilities in forms? What should be the prize to break it turned out to be, roughly speaking, economically feasible? $1000? $10,000? $100,000?
Thanks to all who answered!

Answer 1

then I realized that you can break everything, there would be a desire. =)

Everything is clear, someone has seen enough American films about cool hackers.
This moment usually occurs when the game has more than 3.5 players, regardless of winnings.
Clearly, you don't even understand how it works.

Answer 2

It is enough to have a question-answer base, and input automation is not a problem. Once upon a time, Intel held a quiz, where the bot asked a question and other participants answered. The faster the answer was given, the more points were awarded. So, 2 weeks, and the participants began to use automation. And they did it all in different ways. As a result, the most arrogant one won, who set up his bot for the smallest delay. And the prizes are not bad for those times, up to 700 bucks approximately. It's good that there were three or four stages, and everyone snatched a prize. The answer base was also collected automatically. So ways to bypass or hack can still be found, but not always advisable.

Answer 3

I do not advise, otherwise they will be taken to the Pentagon, and then to Guantanamo Bay.

Answer 4

It is impossible to get the answer from the form, it is not there.
If the question becomes known to the players at the same time as the form appears, you will not be able to automatically enter with a minimum delay, since it is not known what to enter. Brute force if only with handles, since again the question is not known in advance and you cannot make a base for brute force.
In such competitions, I would be more afraid of leaking information to the side from the organizers than hacking Google forms.