No, smoking before an x-ray will not make the x-ray look any different. Chronic long term problems caused by smoking such as emphysema will show up on an chest x-ray.
there is no difference
Plastic surgeons strongly urge adult patients to quit smoking before the surgery, because smoking delays and complicates the healing process.
after
Native Americans were smoking centuries before records were kept.
Smoking forms habit as the smoker used to smoke while drinking his/her coffee or tea, after eating, before sleeping, when watching TV, before and after practicing sexual acts, when going out home, when drinking alcohols, ... etc.The occasions related to smoking make smoking a habit.If the smoker manages to break the tie between smoking and the occasion it would be much easier for the smoker to give up smoking.
The difference in meaning is that the action stated by a present perfect tense may have been completed in the last second of time before the present, while the past perfect implies completion at a substantially earlier time. The formal difference is that the present perfect is formed from the present tense of "have", used as an auxiliary verb, combined with the past participle of the principal verb. For the past perfect tense, the past tense of "have" as the auxiliary verb is combined with the past participle of the principal verb.
Present is now - what is currently happening - and past is anything and everything that has happened (been and gone).
Alot of them
Yes.
Because light moves substantially faster than sound.
Substances that are present before the reaction are called "reactants" or "reagents".
Substances that are present before the reaction are called "reactants" or "reagents".