I am very confused, i am studying ''general least squares,polynomial regression, linear regression, newton's interpolating polynomials, lagrange interpolating polynomials'' now. I have a question but i don't know which method i should use, can you help me quickly? Thanks. This is my question:

Consider the data in the following table for constant-pressure specific heat, C
p (kJ/kg.K) at various temperatures T (K). Determine the simplest interpolating polynomial that is likely to predict Cp within 1% error over the specified range of temperature.
T : 1000 1100 1200 1300 1400 1500
Cp 1.410 1.1573 1.1722 1.1858 1.1982 1.2095