If 250 mg of a radioactive element decays to 190 mg in 24 hours, find the half-life of the element. (round your answer to the nearest whole number.)

61 hours

Explanation:

In this question we will use radioactive decay model

m0= 250 mg

h is the hlf life of element

m(t) is the mass left after t time

so,

solving this equation for h

reaaranging and taking ln on both the sides we get

solving further we get

h= 60.62 hours ≅61 hour

the half life of element is 61 hours

answer; ///i do believe that the correct answer is (b); ///particle composed of two or more atoms bonded together;