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.
The Social Security tax rate is assessed on all types of income earned by an employee including salaries, wages, and bonuses. However, there is an income limit to which the tax rate is applied. For 2017, the Social Security tax is taken from income up to an annual limit of $127,200. Any amount earned above $127,200 is Social Security tax-free.