(a) Namakan keimunan P dan Q.

(b) Terangkan persamaan dan perbezaan antara keimunan P dan keimunan Q.

(c) Pada pandangan anda, keimunan yang manakah lebih baik? Jelaskan jawapan anda.

4. Cadangkan dua amalan yang melemahkan sistem keimunan seseorang.

dadak

the answer for sodium is 0.186

the answer for rubidium is 0.251

acid rain does not usually kill trees directly. instead, it is more likely to weaken the trees by damaging their leaves, limiting the nutrients available to them, or poisoning them with toxic substances slowly released from the soil. the main atmospheric pollutants that affect trees are nitrates and sulphates.