Alexandra decides to climb Mt. Krumpett, which is 5000 m high. She determines that this will require a total of 3600 kcal of energy for the trip. For her food supply, she decides to take nutrition bars. The label states that each bar contains 50 g of carbohydrates, 10 g of fat, and 40 g of protein. How many Nutrition Bars does she need?

The answer to your question is 8 bars

Explanation:

Data

Total energy = 3600 kcal

Content of a bar     50 g Carbohydrates, 10 g of fat and 40g of proteins

amount of energy of Fats          8.8 kcal/g

amount of energy of Proteins and carbohydrates  4 kcal/g

Process

1.- Calculate the energy of each nutrient in the bar

50 g x 4 kcal/g = 200 kcal

10 g x 8.8 kcal/g = 88 kcal

40 g x 4 kcal/g = 160 kcal

Total energy in a bar = 200 + 88 + 160

                                   = 448 kcal

2.- Calculate the number of bars needed

     # of bars = 3600 kcal/448 kcal

     # of bars = 8 bars

  the   balanced   equation   for   reaction of   ca metal   with   o2 to   produce   cao   is as below

2 ca+ o2→ 2 cao2

  explanation

the reaction is   balanced     since the   number of atoms   in reactant side is   equal to   number of atoms   in   product side.   for   example   they   are 2   atom of   ca in   reactant   side   and   2   atoms of ca   in   the product side.

  the   process   is a   meet the   requirement   of   redox   reaction because :     calcium   is   oxidized   from   oxidation state 0   to 2+   while   oxygen   is reduced from   oxidation   state   0   to 2-

i think it's letter a.