Shot glasses aren’t exactly standardized. Some are 1 oz, some 1.5 oz, big ones are usually 2 oz, the list goes on.
In the US, 1.5 oz for a shot is (very) generally the standard measurement, so you can go with that.
A 1.75 liter bottle equals 59.17454 in fluid ounces. Thus, if you are using the standard 1.5 oz shot, you would get just a bit over 39 shots of liquor out of the bottle.
A "standard" drink is any drink that contains about 0.6 fluid ounces or 14 grams of "pure" alcohol. See the approximate number of standard drinks in different sized containers at rethinkingdrinking.niaaa.nih.gov.
To determine blood alcohol content, use the blood alcohol level chart at dui.drivinglaws.org.
To see standard bar measurements, go to www.webtender.com.
Check out practical tips & advice if you've made the decision to stop drinking alcohol, shared by Drinkaware.