What is the formula to criss cross reduce Aluminum bromide

It will appear as o2(g) as a reactant 

Naoh + hbr -> nabr (salt) + h2o ca (oh)2 + 2hbr - - - > ca (br)2 + 2h2o

Answer the same molecular formula;

The main types of electromagnetic radiation. radio  waves have  the lowest frequencies  and  longest  wavelengths, while gamma  waves have highest frequencies  and shortest wavelengths. the wavelengths vary across the electromagnetic spectrum from about 10–15 m to more than 104 m.hope it !