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.
1 Very large stars have a lifespan of only a few million years while very small stars can exist for trillions of years. 2  The lifespan of our own star, the Sun, is around 10 billion years. 3  Supernovas are explosions generated by large stars when they come to the end of their lifespan.range dwarfs are also very common in our galaxy, they generally have a mass of between 0.5 and 0.8 of the sun and have lower surface temperatures. Orange dwarfs stay in the main sequence period of their lifespan up to three times longer than yellow dwarfs such as our sun.