Answer:
42,5 mL
Explanation:
We need to use the serial dilution formula beacuse we start with a stock concentrate solution and we need to prepare a new less concentrated one.

<u>DF in the dilution factor, Vi is the initial volume and Vf is the final volume.</u>
The first step is to have the same measurment unit so we need to convert 345 µg to mg.
we know that 1 µg equals 0,001 g, hence:

now the final volume is 0,345 mg protein/ mL and the inital volume is 15mg protein/mL, both of them are in the same unit so we can use the formula


Now since the question said that we already have 1.0mL of the amylase stock solution we need to subtract that 1.0mL to the 43,5 mg protein/mL

So, we need 42,5 mL of diluting buffer if we want a final concentration of 345 µg protein/mL (0.345 mg protein/mL)
<span>Yes, all living organisms are made of at least one cell (cell theory). But, remember, viruses and prions, which cause diseases, are not technically living things, and they are NOT made of cells. Also, if asked a question similar to this on a biology test, the teacher may be trying for an answer similar to: "Organisms are made of different organ systems, which are made of various related organs, which are made of different tissues working together, which are made of cells". </span>
<span>Many sexually active american adolescents fail to avoid pregnancy because they are not educated on contraceptive methods. </span>
Answer: B: the variety of living things on Earth.
(Biodiversity refers to every living thing, including plants, bacteria, animals, and humans.)