What structure on the south african coast has a range of 63 km and releases flashes every 30 seconds?

What is created when solids, liquids, an gases mix with one another

Ihave a density of 1.61g/cm^3 and a mass of 28g. find the missing value

Beryl states that insulation with the smallest possible thermal conductivity is best to keep a house warm in winter, but worst for keeping a house cool in summer. sapphire insists the reverse is true: low thermal conductivity is good in the summer, but bad in the winter. which one, if either is correct? a. beryl, because low thermal conductivity results in low heat transfer. b. beryl, because low thermal conductivity results in high heat transfer. d. sapphire, because low thermal conductivity results in high heat transfer. e. neither, because low heat transfer is desirable both in summer and in winter.