How you`re supposed to know Chebyshev’s inequality table??

I mean see the exercise:

According to Exhibit 27, the arithmetic mean monthly return and standard deviation of monthly returns on the S&P 500 were 0.95 percent and 5.39 percent, respectively, during the 1926–2017 period, totaling 1,104 monthly observations. Using this information, address the following:

1 Calculate the endpoints of the interval that must contain at least 75 percent of monthly returns according to Chebyshev’s inequality.

How I`m supposed to know that 75 percent is 2 standard deviations??

There`s a table in page 421 that states the percentage or k values of 1,25, 1,5, 2, 2,5 3 4

But how I`m supposed to know how many standard deviation I should put?

WTF