Two springs with spring constants k1 and k2 are put togetherend-to-end. Let x1 be the amount by whichthe rst spring is stretched relative to its equilibrium length, andsimilarly for x2. If the combineddouble spring is stretched by an amount brelativeto its equilibrium length, then b= x1 + x2. Find the spring constant,K, of the combined spring in terms ofk1 and k2.