The first two dog run is 2 meter wide and 4 meter long the second dog run has the same length as the first dog run . The area of the second dog run is half the area of the first dog run what the width is the second dog run

paula, cory, and krista

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:  

your answer is b.

1,333 cubic feet  

and i know this one is right.

the correct answer for this just to make it clear for you guys is 2,3