Which of the sets of ordered pairs represents a function? (5 points) A = {(1, -5). (8,-5), (8, 7), (2, 9)}
B = {(7. -4), (7, -2) (6, -3), (-9, 5)}

only a
only b
both a and b
neither a nor b

pls respond soon

20 points for the brainliest? drag each tile to the correct box. not all tiles will be used. arrange the steps to solve the equation . plz

Ariana starts with 100 milligrams of a radioactive substance. the amount of the substance decreases by 20% each week for a number of weeks, w. the expression 100(1−0.2)w finds the amount of radioactive substance remaining after w weeks. which statement about this expression is true? a) it is the difference between the initial amount and the percent decrease. b) it is the difference between the initial amount and the decay factor after w weeks. c) it is the initial amount raised to the decay factor after w weeks. d) it is the product of the initial amount and the decay factor after w weeks.

Acd that is originally priced at $15.85 red-tagged for the sale. what is the sale price of the cd