The electromagnetic radiation in the order of increasing wavelength is given as
Gamma rays
X rays
Ultra violet rays
Visible radiation
Infrared rays
Microwaves
radiowaves
So, the radiations having wavelength more than the visible radiation are infrared radiations and the radiations which having the wavelength less then the visible radiation is Ultraviolet rays.
So, we observe ultra violet radiations and infrared radiations.
B ) Ascend using my buddy alternative air source / make an emergency Ascent
Explanation:
From the description it can be seen his buddy is close by of which he can easily use the alternative air source. Also we can see that he is closer to the water surface than his buddy, of which controlled emergency swimming ascent is highly favourable in this condition.