DN A radioactive substance of mass N gram decays at the rate of -KN , where k is a
dt
constant. Initially the amount of the substance was 80 gram. After 100 years it decayed to
20 gram
(a) Express N in terms of the elapsed time t.
(b) Calculate the amount of the substance remains after 120 years,

Read the excerpt from the strange case of dr jekyll and mr. hyde what do dr. jekyll's thoughts reveal about him in this excerpt? [t]he inmates of my house were locked in the most rigorous hours of slumber, and i determined, flushed as i was with hope and triumph, to venture in my new shape as far as to my bedroom. i crossed the yard, wherein the constellations looked down upon me, i could have thought, with wonder, the first creature of that sort that their unsleeping vigilance had yet disclosed to he is jealous of those who can sleep through the night. he is revered for his scientific advances. he is interested in studying the movements of the stars he is proud and enthusiastic about his initial results.

Janet is rolling a number cube with the numbers one through six she record the numbers after each row if she rolls of keep 48 times how many times should she expect to roll a 4

What is the value of n in the equation -1/2(2n+4)+6=-9+4(2n+1)