Self-certification. Employers can also ask employees to fill in a form when they return to work to confirm theyâve been off sick for up to 7 days. This is called âself-certificationâ. Employers usually provide their own version of this form.elf-certification. Employers can also ask employees to fill in a form when they return to work to confirm theyâve been off sick for up to 7 days. This is called âself-certificationâ. Employers usually provide their own version of this form.
Â· just now. 1  The most massive stars (OB stars) have the shortest life. K and M stars are the least massive and have the longest lives. 2  McGarnigle is the most correct here. Type O and B are the hottest, most massive stars and, by virtue of their extreme mass, are the shortest lived.
A neutron star, like a white dwarf or black hole, is actually not a star but a stellar remnant. When a massive star reaches the end of its life it undergoes a supernova explosion, leaving behind its incredibly dense core. A soup-can full of neutron star material would have about the same mass as our Moon.