Please help me

Mobistar is a mobile services company that sells 800 phones each week when it charges 80 per phone. It sells 40 more phones per week for each $2 decrease in price. The company's revenue is the product of the number of phones sold and the price of each phone. What price should the company charge to maximize its revenue? Let d represent the number of $2 decreases in price. Let r represent the company's revenue. Write a quadratic function that reflects the company's revenue.

Part B: Find the vertex of the quadratic function above. How will finding the vertex help you determine at what price the company should charge to maximize its revenue?

Part C: Graph this function and show in the graph what price should the company charge.

ιт ιѕ 6 6/23

step-by-step explanation:

нσρє ι ¢συℓ∂ нєℓρ уσυ συт

in 2010, the population of the state of california is 37.29 × 10⁶

step-by-step explanation:

population of los angeles = 3.79 × 10⁶

population of california = 9.84 × population of los angeles

                                        = 9.84 × 3.79 × 10⁶

                                        = 37.2936 × 10⁶

                                        = 37.29 × 10⁶

∴ in 2010, the population of the state of california is 37.29 × 10⁶

the transitive property of equality.

step-by-step explanation:

the correct answer is:

the transitive property of equality.

explanation:

we know that  ∠bcd is congruent to  ∠pbc. we also know that  ∠pbc is congruent to  ∠bad.

we can substitute  ∠bad for  ∠pbc in the first angle congruence statement to give us:

∠bcd is congruent to  ∠bad.

algebraically, the transitive property states if a=b and b=c, then a=c. it basically allows us to substitute equal values. since that is what we did, this is the transitive property.

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