No calculator allowed: which of the following numbers are in the range of f if f(x) = 2x-1 / x+1.
[part of question] : i. -1
ii. 1
iii. 2

i kind of understand but it's tough without a calculator (for me at least). how would you solve these without a calculator?

9.4.34  question   to estimate the height of a stone  figure, an observer holds a small square up to her eyes and walks backward from the figure. she stops when the bottom of the figure aligns with the bottom edge of the  square, and when the top of the figure aligns with the top edge of the square. her eye level is 1.811.81 m from the ground. she is 3.703.70 m from the figure. what is the height of the figure to the nearest hundredth of a  meter?