Which of the following could not be achieved by using science models?

predicting a future value

showing a relationship

comparing the sizes of two objects

proving that an object exists

question 18

what is the scientist's next step, if the experiment shows that the scientist’s hypothesis is false?

change the data to make the hypothesis look true.

ignore the data and report the hypothesis as true.

make a new hypothesis and run a new experiment.

change the hypothesis to match the experiment’s results.

I am absolutely sure that the following which could not be achieved by using science models is proving that an object exists. Unfortunately, you can often come across a lot of information that consists of things which can't be explained by they are in use. It can be either abstract points or objects which state of aggregation can't be measured.
And what about the second one, the scientist's next step, if the experiment shows that the scientist’s hypothesis is false should be :Make a new hypothesis and run a new experiment. When something goes wrong, scientist use the same data but in other way, trying to improve the obtained datum, but if it doesn't fit they don't give up and go on making new experiments :) 

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