What is the main type of radiation that the ozone layer protects organisms from? a. infrared b. ultraviolet c. visible light d. microwaves

Which statement is true about ionic compounds?

Geothermal energy for industrial use is available almost anywhere. a.true b.false

The content of manganese (mn) in steel was determined spectrophotometrically and with the use of the standard addition method. an unknown sample of mn from a digested steel sample gave an absorbance of 0.185 when analyzed spectrophotometrically. when 5.00 ml of solution containing 95.5 ppm mn was added to 50.0 ml of the unknown steel solution (digested sample), the absorbance was 0.248. calculate the concentration, in parts-per-million (ppm), of mn in the digested steel sample solution.