Answer :
First, identify the variables involve. From the given function, f(60) = 210. The value of x is 60 and the value of f(x) is 210. Therefore, the sunflower plant is 60 days old and its height, in cm, is 210. The answer for this item is hence, letter B.
To solve this problem, we first identify the variables that are involved in the problem. We are given the function, f(60) = 210. From this, we can say that at the value of x equal to 60 the function is equal to 210. Therefore, the correct answer among the choices listed is option B. The height of the sunflower plant is 210 cm when it is 60 days old.