It was hard to me.
Especially the first one.
It was the hardest for me (not that up on population genetics and all their formulas). Once I saw "... the Hardy-Weinberg equation, the term 2pq represents ... " I figured that the full equation is
p^2 + 2pq + q^2
where p is one allele and q the other allele, so pq is heterozygous and the others are homozygous,
The equation with R = 0.8 (making w = .02) is
(0.8)^2 + 2(0.8)(0.2) + (0.2)^2
= 0.64 + 0.32 + 0.04
But I did a little grid to figure it out:
| w
| R
| R
| R
| R
|
w
| ww
| Rw
| Rw
| Rw
| Rw
|
R
| Rw
| RR
| RR
| RR
| RR
|
R
| Rw
| RR
| RR
| RR
| RR
|
R
| Rw
| RR
| RR
| RR
| RR
|
R
| Rw
| RR
| RR
| RR
| RR
|
Σ(RR) = 4x4 = 16
Σ(Rw) = 2x4 = 8
Σ(ww) = 1x1 = 1
Σ(all) = 5x5 = 25 (check)
16/25 = 64%
8/25 = 32%
1/25 = 4%
It took me longer to dB code this that to scratch it out on an envelope (literally).
Enjoy