Overview. Beryllium is the lightest member of the alkaline earth metals family. These metals make up Group 2 (IIA) of the periodic table. They include beryllium, magnesium, calcium, strontium, barium, and radium.Elements in the same column of the periodic table have similar chemical properties.eryllium is the lightest member of the alkaline earth metals family. These metals make up Group 2 (IIA) of the periodic table.
Definition 1: EER, energy efficiency ratio: Is the measure of air conditioner efficiency at maximum air conditioning load. It is measured by ratio of Btu/hour of cooling or heating load, to watts of electrical power input. The unit is in Btu hr-1 W-1. Definition 2: SEER, seasonal energy efficiency ratio: The measurement units of SEER is exactly the same as EER, but the difference lies in the data used for the measurement. Values for SEER, is determined through averaging readings of different air conditions, to represent air conditioner efficiency throughout the season.
The IRR is the interest rate, also called the discount rate, that is required to bring the net present value (NPV) to zero. That is, the interest rate that would result in the present value of the capital investment, or cash outflow, being equal to the value of the total returns over time, or cash inflow.ecause of the time value of the dollar, the IRR calculation can be very simple or very complicated depending on the project in question. Calculating the IRR for a one-year project with a single lump-sum capital investment and single payout is fairly straightforward.