Thea does not remember in what order she added the ingredients but the last thing she added was 6- 1/4tsp. (6-quarter teaspoons). Select the only option(s) from the checklist below that could have been the last ingredient. * Cinnamon Baking Soda Pure Vanilla Extract Salt Cream of Tartar

Step-by-step explanation:

From the given ingredient the recipe is meant for cinnamon-sugar cookies

Given the list

(Cinnamon, Baking Soda, Pure Vanilla Extract, Salt ,Cream of Tartar)

With me here is a typical recipe for the baking of cinnamon-sugar cookies  

1 cup C&H® Golden Brown Sugar

½ cup C&H® Granulated Sugar

½ cup (1 stick) Unsalted butter, softened

1 teaspoon Pure vanilla extract

2 large eggs

2 ½ cups All-purpose flour

1 teaspoon Cream of tartar

½ teaspoon Baking soda

¼ teaspoon salt

2 tablespoons Granulated Sugar

2 teaspoons ground cinnamon

Now 6- 1/4tsp. corresponds to 6(0.25)=1.5tsp

1.5tsp  is a close approximation of  2 teaspoons Ground cinnamon in our typical recipe, hence we could predict that Thea added Cinnamon last

ou would have 12 of each