I'd love some help! In each trial, add an indicator to the mystery food sample. But also add the indicator to a known substance and water. Why is that important? Check all reasons.

A. To practice measuring volume using the graduated pipette correctly.

B. To match the mystery food sample to a definite positive result (gelatin, oil, etc.).

C. To match the mystery food sample to a definite negative result (water).

D. To increase the amount of data.

The test above showstest for the mystery food sample.
what is the blank?
A. Positive?
B. Negitave?
C. Iconclusive?

Thanks

For the first question, the reasons should be:

B. to match the mystery food sample to a definite positive result (gelatin, oil, etc.)

C. to match the mystery food sample to a definite negative result (water)

For the second fill-in- the blank:

The test above shows B. negative for the mystery food sample.

the first person is right !!

Explanation:

i did what they said to and i got it correct !!

blood enters the heart through two large veins, the inferior and superior vena cava, emptying oxygen-poor blood from the body into the right atrium of the heart. as the ventricle contracts, blood leaves the heart through the pulmonic valve, into the pulmonary artery and to the lungs where it is oxygenated.