The human body (can/cannot) produce all the amino acids.

only 10 out of 20

Explanation:

Humans can produce 10 of the 20 amino acids. The others must be supplied in the food. ... The essential amino acids are arginine (required for the young, but not for adults), histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine. These amino acids are required in the diet.

the index of refraction of the second medium is higher. i just took the test trust me !

you didn't give any options but heres what i can tell you: an inference is likely to change based on additional observations. the latter is something that you have seen or sensed using your sensory organs while the former is like a conclusion out from what you have observed.