The electron microscope was invented in germany during the 1930's by
anton van leeuwenhoek
robert hooke
hans and zaccharias janssen
charles spencer
max knott and ernst ruska
spencer, maybe?

yes

no

blue is scattered more than other colors because it travels as shorter, smaller waves. this is why we see a blue sky most of the time.

these muscles maintain the blood pressure in the vessels. the smooth muscles are innervated by nerves of the autonomic nervous system. when the muscles contract, they cause vasoconstriction of the vessels and increase blood pressure. when the muscles relax, they enable vasodilation of the   blood vessels hence reduce blood pressure.