Upper and Lower Bounds

Question 1:

Find the lower bound of 0.831 rounded to 3 d.p.
0.8305

Question 2:

Find the lower bound of 800 rounded to 1 s.f.
750

Question 3:

Find the lower bound of 43.7 rounded to 3 s.f.
43.65

Question 4:

Find the lower bound of 0.262 rounded to 3 d.p.
0.2615