Part A: Which of the following conditions helps to prove quadrilateral ADBC is a kite?
Part B: Melissa designed the kite shown and would like to know
the minimum amount of fabric needed to cover the kite. Each unit
is 1 inch

ending amount = beginning amount / (2^n)

where "n" = number of half-lives (or elapsed time / half-life)

ending amount = 50 mg / (2 ^10 / 5.3)

ending amount = 50 mg / (2 ^ 1.8867924528)

ending amount = 50 m / 3.6981210597

ending amount = 13.5203794557 mg

or about 13.5 mg remain

source:  

answer is b chief keef

get this one right