Can someone please help me on B

Nice work on getting part (a) correct.

To complete part (b), we plug x = 8 into the derivative calculated for part (a)

47 goes in the box

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As for the multiple choice section, you have chosen the correct answer. It is choice C.

f ' (8) = 47 can be interpreted as "at exactly 8 words, the memorization time is increasing by exactly 47 seconds per word".

Phrased another way, it's taking 47 seconds longer to memorize another word at exactly the x = 8 word marker.

answer: the price of one pound cabbage = $ 0.8

the point (10,8) represents that the cost of 10 pounds cabbage is $ 8

step-by-step explanation:

since, here is a proportional relation between the number of pounds of cabbage (x) and the price in dollars (y).

therefore, we can write,

⇒ y = k x

where k is the constant of proportionality.

now, point (5,4) is in the line.

thus, it will satisfies the above equation of line.

⇒ 4 = 5 k

⇒ k = 0.8

thus, the equation of the line is,

y = 0.8 x

a) for x = 1,

y = 0.8

therefore, the cost of one pound of cabbage is 0.8 dollars.

b) in the below graph (10,8) represents that the cost of 10 pounds of cabbage is 8 dollars.

step-by-step explanation: