Impossible to observe: bacteria, viruses, molecules, atoms, and at the other end of the size continuum, mountains, landforms, planets, etc.
Very Difficult: human eggs, large single cells of other kinds
Rather Difficult: crystals of many organic chemicals, fine details of fibers and papers, insect eyes and many others
This depends on which context you are using 'does good' in. For example, if you said that a person 'does good' things, it would be grammatically correct. But if you said someone 'does good' without inferring that they are doing good THINGS, and not just GOOD, then it would not be using correct English. Isn't the English language confusing at times?!? :)
Red blood cells would not be a good source to observe dividing cells in an adult, as they do not contain a nucleus and therefore cannot undergo cell division.
it depends who that person is but my opinion would good because they have cheap things and good things.
small size portable
Blood is one of the good things.
salt and sugar
A good hook would be like a almost a gist or a tiny summary
Using your imagination you can get an idea of what things can be like.
Try different things and when you get good at it you would know.
good things they make things work. bad things they cost a lot and die and they leak stuff like acid and metal and kill people and destroy them and they die :( that's y u shud get rechargable :D
we do not need to study
a person who had good health would be good at athletic things as well as mental thing because when a person is in good health they will be able to move around and will have more energy to do more mental things