1) Maggie shook 100 pennies in a container and counted how many landed heads up. Approximately what fraction of pennies would you expect to land heads up? a) 1/4

b) 1/2

c) 3/4

d) 4/4

2) If three half-lives have passed, what fraction of the isotopes will still be parents?

a) 1/2

b) 1/4

c) 1/8

d) 1/16

3) A sample has a half-life of 1000 years. 1/4 of the isotopes are parents. How old is it?

a) 250 years

b) 500 years

c) 2000 years

d) 4000 years

4) A sample has a half-life of 1 million years. 1/8 of the isotopes are parents. How old is it?

a) 250,000 years

b) 500,000 years

c) 2 million years

d) 3 million years

(answer all and I will mark your answer the brainliest or you can just answer one)

step-by-step explanation:

answer: plz give a pic and answer choices so i can answer!

step-by-step explanation:

the correct answer option is (2x-3)(2x+3).

step-by-step explanation:

we are given the following expression and we are to factorize it:

we are to find such factors that when multiplied they give a result of 36 (9 x 4 = 36) and when added they give a result of 0.

the two such factors of 36 are negative six and postive six.

factorizing the given expression to get:

therefore, the correct factorization of is (2x-3)(2x+3).

this is a direct variation proportion. y = kx

y is the total amount due, k is the constant of variation, and x is the number of texts sent.

plug in the 3.20 and the 16 to solve for the "k". this is the constant of proportionality. it is the value that will not change.

3.20 = k(16). solving you get $.20 per text.

the equation would then be y = .20x