The number of basic headphones the store can purchase if it spends a total of $10,000 on headphones and buys 110 hd headphones for $70 each.

Total amount spent = $10,000

Cost of one HD headphones = $70

So, cost of 110 HD headphones = dollars

Hence, amount left to purchase basic headphones = dollars

So, the store can buy x headphones from $2300. Where x can be found by dividing 2300 by the cost of 1 headphones.

use an equation of ratios to determine the amount of gas needed to fill the tank.

    0.2             0.8

  =    

288.75             x

                                                              231 gal

so, 0.2x = (0.8)(288.75 gal), and x = = 1155 gal.

                                                                0.2

it would take 1155 gal. to fill the tank.

the cost would be

1155 gal         $3

* = $3465   (answer)

      1           1 gal

hope this you

the answer is b.

64

step-by-step explanation:

c=2πr=2·π·8≈64