The hydrogenosome is a crucial organelle for some organisms that inhabit oxygen-poor environments, protists such as some free-living ciliates, unicellular parasites, termite flagellates and rumen fungi and rumen ciliates (Figs. 22.3 and 22.7). These organisms lack conventional mitochondria (Figs. 22.1 and 22.2).
1 Percentage Method. 2  The percentage method taxes a bonus at a flat rate, normally 25%. 3  If the bonus is in excess of $1 million, it is taxed at a rate of 39.6%. 4  This means that if your bonus is $10,000, and you are taxed using the percentage method, $2,500 goes to the IRS.
Social Security tax is one part of the Federal Insurance Contribution Act (FICA) tax, and it is assessed at a rate of 12.4%. This is split evenly between the employee and employer, and it applies to earned income up to $118,500 for 2016 -- resulting in a maximum Social Security tax of $14,694. The remainder of FICA tax goes to Medicare.