<span>The correct answer should be a genetic drift. Mutations usually occur over a relatively short period of time and usually start with a single unit that transfers the mutation when they procreate. Genetic drifts separate entire populations and in time create new species that cannot procreate with the original species from whence they came.</span>
<h2>
a) Equivalent resistance is 143 Ω</h2><h2>
b) Potential difference is 71.5 V</h2>
Explanation:
When resistors are connected in series, effective resistance is given by

Here
R₁ = 21Ω
R₂ = 58Ω
R₃ = 64Ω
a) 
Equivalent resistance is 143 Ω
b) We know
Potential difference = Current x Resistance
V = IR
I = 0.5 A
R = 143Ω
Substituting
V = 0.5 x 143 = 71.5 V
Potential difference is 71.5 V
The answer you have is right good job 12
The answer would be stage of<span> conversion of Hydrogen to Helium.
At the end of this phase, the helium content of the suns will have the popping effect where more and more helium is now on the core resulting to higher temp and density as helium converted from hydrogen is much heavier.</span>