Answer:
The answer to this question is D.
Explanation: We know that only plants have a cell wall so that is helpful and we know that plants are green because of their chloroplast. So the answer is D, cell wall, and chloroplast.
Answer:
0.72 g of the lower oxide gave 0.8 g of higher oxide when oxidised. ... Thus, 90g of lower oxide contains as much metal as 100g of higher oxide, i.e., 80g (given). Hence, 80g of metal combines with 10g of oxygen in the lower oxide and 20g of oxygen in the higher oxide.