The can increase and decrease in size to monitor the amount of light entering the eye.

I’m not sure but I’m pretty sure it’s the pupil because that’s what happens to me I see it change shape

The pupils.

When there is less light the pupil expands so it has a bigger chance of capturing light. When there is more light it decreases in size because it's easier to capture light and not much effort is needed.

Hope it helped!

This is what i did 45-5=4040÷4=10so there are 10 white marbles but am not sure is just a question that am not sure

Very hard to understand