clc(); clear; //Given : h = 1.05*10^-34; //planck's constant in Js m = 9.1*10^-31; //electron rest mass in kg c = 3*10^8; //Speed of light in m/s b = 1.7*10^-15; // range of nuclear force in m m_pi = h/(b*c); // rest mass of a pion in kg t = m_pi/m; // times the rest mass of an electron printf("Rest mass of a pion is %d times the rest mass of an electron",t); // textbook answer is 220 , because approximate value for m_pi was considered.