Going by the formula, Half-Life = ln(.5) / k
Half-Life = .693147 / .1205
Half-Life = 5.75 days and rounded to nearest tenth,
Half-Life = 5.8 days
For the 2nd question......is it correct????? Because the area of square is s.s and area of rectangle is l.b
is 3 units from 
Explanation:
To find distance between two points always take absolute value.

So, to find how many units -4 from -1 is,

Learn more:
brainly.com/question/12928519
Answer: i think its the 2 one
step by step explanation: