Hi folks ! Here is my solution until point 8.
Your comments are welcomed 
// Returns a random DNA base
const returnRandBase = () => {
const dnaBases = ['A', 'T', 'C', 'G']
return dnaBases[Math.floor(Math.random() * 4)]
}
// Returns a random single strand of DNA containing 15 bases
const mockUpStrand = () => {
const newStrand = []
for (let i = 0; i < 15; i++) {
newStrand.push(returnRandBase())
}
return newStrand
}
function pAequorFactory(specimenNum , dna) {
return {
specimenNum,
dna,
mutate () {
const index=Math.floor(Math.random() * 15);
let newbase=returnRandBase();
while (newbase===this.dna[index]) {
newbase=returnRandBase();
};
this.dna[index]=newbase;
return this.dna;
},
compareDNA (pAequor) {
let count = 0;
for (let i=0;i<pAequor.dna.length-1;i++) {
if (pAequor.dna[i]===this.dna[i]) count++;
}
const commonDnaPct=(100*count/pAequor.dna.length).toFixed();
return `specimen ${this.specimenNum} and specimen ${pAequor.specimenNum} have ${commonDnaPct}% DNA`;
},
willLikelySurvive() {
let count = 0;
for (let i=0;i<this.dna.length-1;i++) {
const currentbase=this.dna[i];
if (currentbase==='C'||currentbase==='G') count++;
};
const result = Math.floor(100*count/this.dna.length);
return (result>=60);
}
};
}
const pAequor = pAequorFactory(1, mockUpStrand());
console.log(pAequor);
const pAequor2 = pAequorFactory(2, pAequor.mutate());
console.log(pAequor2);
console.log(pAequor.compareDNA(pAequor2));
const pAequor3 = pAequorFactory(3,
[ 'G', 'G', 'A', 'C', 'C', 'C', 'C', 'C', 'A', 'C', 'C', 'T', 'T', 'T', 'A' ]
);
console.log(pAequor3.willLikelySurvive());
const pAequorArrayToStudy = [];
for (let i=0; i<30; i++) {
let newpAequor = pAequorFactory(i+1, mockUpStrand());
while (!newpAequor.willLikelySurvive())
newpAequor = pAequorFactory(i+1, mockUpStrand());
pAequorArrayToStudy.push(newpAequor);
}
console.log(pAequorArrayToStudy);
