CalculusHard ShareCalculus · Hard problemA substance decays according to dydt=−ky\dfrac{dy}{dt}=-kydtdy=−ky with half-life 555 years. Find kkk.A5ln2\dfrac{5}{\ln 2}ln25Bln45\dfrac{\ln 4}{5}5ln4Cln26\dfrac{\ln 2}{6}6ln2Dln25\dfrac{\ln 2}{5}5ln2Check Show answer Walk through it step by step Practice more like this