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.
Best Answer: A star's lifespan is determined almost entirely by its mass. The more massive a star is, the hotter it burns, the brighter and bluer it is, and the shorter its lifespan. The logest-lived stars are the least massive, which are also the dimmest. The most massive stars (OB stars) have the shortest life. K and M stars are the least massive and have the longest lives. The more massive a star is the shorter it's life as it will burn its fuel up at a greater rate. 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.