Which objects cannot be observed in detail without a microscope? Choose more than one answer.

A) Red blood cell
B) Dinosaur fossil
C) Bacterium
D) Snowflake
E) Volcanic rock
F) Dust particle

thats a little if u want the answer just look it up on google thats what i do haha : )

a gas, having a molecular weight of 13 kg/kmol and a kinematic viscosity of 0.25 cm2/s, flows through a pipe 0.25 m internal diameter and 5 km long at the rate of 0.4 m3/s and is delivered at atmospheric pressure.

nacl or sodium chloride is an ionic compound. this is because an ionic compound pertains to a compound that consists of positively and negatively charged ions. in this case, na (sodium) has a tendency to lose one electron when it reacts with with other atoms, so the resulting sodium ion contains 11 protons and 10 electrons, thus making it positively charged (na+), when chlorine reacts, it usually gains one electron to form an ion called chloride, thus making it negatively charged ( since the ions are oppositely charged, they attract.

може ли да зареждате повече информация, моля