You have not provided the options, therefore, I cannot give an exact answer. However, I can help you with the procedures.
We are given that the ratio between the width and the length of the flag is 10 to 19.
This means that:

Therefore, to get the correct choice, all you have to do is divide the width by the length, if the result is 10/19, then the dimensions given are correct.
Examples:For length = 190 and width = 100,
width / length = 100 / 190 = 10 / 19 .........> correct choice
For length = 1.9 and width = 1,
width / length = 1 / 1.9 = 10 / 19 .......> correct choice
Hope this helps :)
Converted to a decimal it’s -0.8
Answer:
<h2>Option A</h2>
Step-by-step explanation:
<h3>To round to ONE decimal place means one significant number should be after the decimal point (.)</h3><h3>Option A is the correct answer because if I a zero leads after the decimal point then it isn't significant.</h3><h3>The zero in option A is insignificant but other numbers are and it says to ONE decimal place so option A is the correct answer.</h3><h3>Hope this helps.</h3>
Good luck ✅.