We would divide the shape into a rectangle and a trapezium
The rectangle is of length, 24.5 ft and width 10.75 ft
Area = 24.5 * 10.75 = 263.375 square feet.
Trapezium : Parallel sides are 18.5 ft and 24.5 ft
Height: 12 - 10.75 = 1.25ft
Area of Trapezium = (1/2)*(Sum of Parallel sides)*height
= 1/2 * (18.5+24.5)* 1.25
= 1/2 * 43* 1.25 = 26.875
Total Area = Area of Rectangle + Area of Trapezium
= 263.375 + 26.875 = 290.25
Area = 290.25 ft² (D)
Trinomial is the ancer to the first one
After 1 hour, 360 g decays to 180 g.
After another hour (total 2 hours), 180 g decays to 90 g.
After another hour (total 3), 90 g decays to 45 g.
After one more (total 4), 45 g decays to 22.5 g.
More quickly, with a half-life of 1 hour, the 360 g of starting material decays to
(360 g) / 2⁴ = 22.5 g
In general, if the half-life is 1 hour, then after <em>n</em> hours, an initial amount <em>A</em> of this substance decays according to
<em>A</em> / 2<em>ⁿ</em>
