For a submarine cable, the range of signalling is governed by the function f(r) = r^2 ln⁡(1/r)

where 0
Find df/dr.

Step-by-step explanation:

Explanation

Given function f(r) = r² log r  ....(i)

Apply derivatives formula

Differentiating equation (i) with respective to 'r' , we get

Final answer:-                

change of stock price/initial stock price on friday * total stock value = change of stock value

0.89/73.73 *x = 42.72

x=3539.04 = total stock value at initial stock price on friday .

total stock value at initial stock price on friday/ initial stock price on friday = number of shares

3539.04/73.73 = 48 shares

they own 48 shares of this stock