PLEASE HELP!!! You pick a card at random. Without putting the first card back, you pick a second card at
random.
1 2 3 4
What is the probability of picking a 1 and then picking a 4?
Write your answer as a fraction or whole number.

Check all that apply. f is a function. f is a one-to-one function. c is a function. c is a one-to-one function.

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.

Solve the following system of equations express your answer as an ordered pair in the format (a,b) with no spaces between the numbers of symbols 5x+2y=22