All Answers (8) 1  This is nice information from wikipedia visit. 2  I guess if you assume the DNA is at rest with an average rise of 3.4 A per base pair, then the length of chr1 would be 3.4A * 249*10^6, i.e. 847*10^6A, i.e. ~85 mm, or 8.5 cm.
Boiler sizing includes two things: 1  The heating and hot water capabilities of the boiler. 2  The physical size of your boiler and whether it will fit in the space you have it destined for.
Every set of tubes that the flue gas travels through is considered a âpassâ. Boilers designed for three-passes have the stack at the rear, and boilers designed for four-passes have the stack at the front. A boiler with more passes has a higher heat extraction rate and is more efficient then one with less passes. Watertube boilers are safer by design and generally can operate many years longer than firetube boilers.