Two test tubes are filled with a solution of bromthymol blue. a student exhales through a straw into each tube, and the bromthymol blue turns yellow. an aquatic green plant is placed in each tube, and the tubes are corked. one tube is placed in the dark, and the other tube is placed in direct sunlight. the yellow solution in the tube in sunlight turns blue, while the one in the dark remains yellow. which statement best explains why the solution in the tube placed in sunlight returns to a blue color?
question 11 options:

oxygen was produced by photosynthesis.

oxygen was removed by respiration.

carbon dioxide was removed by photosynthesis.

carbon dioxide was produced by respiration.

The correct answer is oxygen was produced by photosynthesis.

Explanation:

During the process of photosynthesis carbon dioxide is consumed and oxygen is released in presence of sunlight.

    when plant is placed in the yellow solution and kept in sunlight the plant undergo photosynthesis.As a result the yellow solution in the tube in presence of sunlight turns blue because oxygen is released by reduction which is responsible for the blue coloration of the solution.

  On the other hand the plant that is placed in dark unable to undergo photosynthesis due to which there is no change in color.

39.82 %

Explanation:

Proteins and carbohydrates provide 4 calories per gram. On the other hand, fats provide 9 calories.

We can first calculate the calories of protein + carbohydrates:

       (30g + 4g) x 4 = 136 calories

And we must calculate the calories provided by fat:

        10g x 9 = 90 calories

Now to get the percentage we must see how many calories the dessert has in total:

          136 + 90 = 226 cal

This represents 100% of calories. And now we need to find out how much 90 calories are from the total.

           226 cal > 100%

             90 cal > X

       (90 x 100) / 226 = 39.82 %