choose all which define events a and b as independent events.

p(a) = 0.6, p(b) = 0.4,  p(a& b) = 0.24

p(a) = 0.3, p(b) = 0.4,  p(a& b) = 0.70

p(a) = 0.5, p(b) = 0.1,  p(a& b) = 0.60

p(a) = 0.3, p(b) = 0.2,  p(a& b) = 0.06

There are 2 answers: Choice 1, Choice 4

Why is this? Because we use the rule

P(A & B) = P(A) * P(B)

which only works if events A and B are independent

For the first answer choice,

P(A) * P(B) = 0.6*0.4 = 0.24 = P(A & B)

so that matches.

The same applies to the fourth answer choice as well

P(A) * P(B) = 0.3*0.2= 0.06 = P(A & B)

The other answer choices don't match up.

The second answer choice has

P(A) * P(B) = 0.3*0.4 = 0.12 but that doesn't match with the 0.70 given

Similarly for the third answer choice,

P(A) * P(B) = 0.5*0.1 = 0.05 which doesn't match with the 0.60

answer is 1

step-by-step explanation:

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

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