Please someone help me with these! Mark brainliest !

4.) Cost of cordless phone = $55

cost of each additional handset = $25  

Therefore, the overall cost of the cordless phone, including the 3 extra handsets is:

$55 + 3($25) = $55 + $75 = $130

5.) Given the function, f(d ) = .20d + 14, where:

f(d) = global temperature (in Celsius)

d = number of decades  

To evaluate the value of f (d ) at f(10), you'll have to substitute the value of d = 10 as input into the function:

f(10) = .20(10) + 14

f(10) = 2 + 14

f(10) = 16

6.) Value of f(10):

    In 10 decades, the predicted global temperature will be 16° Celsius.

7.) The correct answer is B. The global temperature f(d) depends on the number of decades, d.

Explanation: the independent variable is d →  it is the input of the function. The output primarily depends on the given value of input.

8.) Given the function, f(t ) = 0.2t

where t = represents number of days elapsed since the planting of the seed.

         Evaluate f(40):

        f(40) = 0.2(40)

        f(40) = 8

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