Please help guys the question is give reasons

a. we have to separate the mixture

b. All impure substances are not harmful.

c. A mixture of iron fillings and sand can be separated by using a magnet

d. A sentences "shake before well use" is written on the bottle of the medicine.

If you chip a tooth, most likely you will go to the dentist to have the missing material filled in. currently the material used to fill in teeth is a polymer that is flexible when put in, yet is hardened to the strength of a tooth after irradiation with blue light at a wavelength of 461 nm. what is the energy in joules for a photon of light at this wavelength?

Draw two cyclic constitutional isomers of cis-1

How many moles of sulfuric acid (h2so4) are needed to react completely with 6.8 moles of lithium hydroxide (lioh)? 2lioh + h2so4 → li2so4 + 2h2o a. 3.4 mol h2so4b. 6.8 mol h2so4 c. 10.2 mol h2so4 d. 13.6 mol h2so4