The answer is 40.
We can solve this by finding out the number of protons, and neutrons. Atomic number of an element means the number of protons in that element. So, the atom has 30 protons if the atomic number is 30.
On the other hand, mass number is the total number of protons and neutrons, but not electrons, because they're too light comparing to the other 2. Therefore, we can simply solve the number of neutrons in the atom by subtracting the number of protons from the mass number. 70 - 30 = 40.
Therfore, the number of neutrons is 40.
Answer:

Explanation:
Hello!
In this case, we can divide the problem in two steps:
1. Dilution to 278 mL: here, the initial concentration and volume are 1.20 M and 52.0 mL respectively, and a final volume of 278 mL, it means that the moles remain the same so we can write:

So we solve for C2:

2. Now, since 111 mL of water is added, we compute the final volume, V3:

So, the final concentration of the 139 mL portion is:

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<h3>Question :</h3>
The use of genetics by farmers to produce more abundant and healthier crops is an application of the science of _____.
<h3>Answer :</h3>
The use of genetics by farmers to produce more abundant and healthier crops is an application of the science of <u>biotechnology</u>.
So correct option is 2nd biotechnology.
<h3>Explanation :</h3>
Biotechnology is the use of biological structures and processes for useful industrial purposes, whether product or function.
Answer:
Explanation: So 1 Kelvin is equal to -272.15 Celsius. Now we need to do some math,
563,180 x -272.15 = -153,269,437 Celsius
I hope this helps :)