17 Based on the graph, what is the approximate number of radioactive atoms of Isotope X that are present when 8 hours of decay has occurred?
(A) 90
(B) 115
(C) 155
(D) 200

You and a group of friends are spending your vacation hiking through the mountains. it is cold in the mountains. you will be expending a lot of energy while hiking and you will need plenty of energy to keep you warm. you should pack foods high in to provide the most energy or kilocalories per gram of food. a) carbohydrates b) lipids (fats) c) proteins d) sugars