Acertain element has a half life of 4.5 billion years. a. you find a rock containing a mixture of the element and lead. you determine that 60% of the original element remains; the other 40% decayed into lead. how old is the rock? b. analysis of another rock shows that it contains 5% of its original element; the other 95% decayed into lead. how old is the rock?

step-by-step explanation:

the answer is 54 sq. ft. i just did this question, on odyssey ware, and it was right. make brainliest.

a) at most means it can cost $12 or less

so the inequality sign would be ≤

you would then need to multiply the number of toppings by the 0.35 for each one and add it to the cost of the cheese pizza.

the equation would be 9.99 + 0.35x ≤ 12

b) using the above equation:

9.99 + 0.35x ≤ 12

subtract 9.99 from each side:

0.35x ≤2.01

divide both sides by 0.35:

x ≤ 2.01 / 0.35

x ≤5.74

at most you could have 5 toppings.

the 5 topping pizza would cost: 0.35 x 5 = 1.75 + 9.99 = $11.74