Anumber changed to 12.6 after it was rounded to what place was the number rounded what would the answer be

Given the following sampling distribution of one mean with a sample size 49, from a normally distributed population,find the population standard deviation, o.79828588912497

Astick 2 m long is placed vertically at point b. the top of the stick is in line with the top of a tree as seen from point a, which is 3 m from the stick and 30 m from the tree. how tall is the tree?

Can someone me with my math problem pls my teacher is on my back about this