Drinking water Technology, Eawag, developed a method by which hazard maps could be produced for geogenic toxic substances in groundwater. This provides an efficient way of determining which wells should be tested. Parameters for drinking water quality typically fall within three categories: Physical and chemical parameters include heavy metals, trace organic compounds, total suspended solids (TSS), and turbidity. Microbiological parameters include Coliform bacteria, "E. coli", and specific pathogenic species of bacteria (such as cholera-causing "Vibrio cholerae"), viruses, and protozoan parasites. Chemical parameters tend to pose more of a chronic health risk through buildup of heavy metals although some components like nitrates/nitrites and
Yield to maturity your initial investment. Your gain is 0 and so is your yield to maturity. For bonds with multiple coupons, it is not generally possible to solve for yield in terms of price algebraically. A numerical root-finding technique such as Newton's method must be used to approximate the yield, which renders the present value of future cash flows equal to the bond price. With varying coupons the general discounting rule should be applied. Yield to maturity The yield to maturity (YTM), book yield or redemption yield of a bond or other fixed-interest security, such as gilts, is the (theoretical) internal rate