Arsenic is a metalloid. A metalloid is an element that has properties of both metals and non-metals. Metalloids occur in the periodic table on either side of the staircase line that starts between boron and aluminum. When heated in air, arsenic combines with oxygen to form arsenic oxide (As 2 O 3).he toxic properties of arsenic compounds made them useful as rat poison. However, they are seldom used for this purpose today. Safer compounds are used that do not present a threat to humans, pets, and the environment. Today, the most important use of arsenic is in the preservation of wood.
According to California Women, Infants and Children Association, one flight of stairs averages 10 steps with a variable of the number of steps on the landings between floors. The number of calories burned climbing 90 steps plus the landing will depend on your how much you weigh and how fast you climb the stairs.
1926.1052(a)(2) Stairs shall be installed between 30 deg. and 50 deg. from horizontal. 1926.1052(a)(3) Riser height and tread depth shall be uniform within each flight of stairs, including any foundation structure used as one or more treads of the stairs.