Step-by-step explanation:
I hope you are 100% clear.
Right answer is B. If we have f equal the amount of her remaining way so f it will be the difference between the way she has gone and her finish line. So we have 70 in the approximate middle of her way and F is between 70 feet and 105 feet, so 105=70+F
Well If you mean't 15 1/2 it is 15.5 This is because a decimal is made for parting using place values like tenths, hundredths, thousandths, etc. The 1/2 part is is .5 because 5 is half of 10.
*I explained a bit more in the comments of my answer.
