Mg reducing agent and Cu oxidising agent.
First, we need to compute the mass of oxygen found in 100 grams of saltpeter:
mass of oxygen = 100 - (mass of potassium + mass of nitrogen)
= 100 - (38.67 + 13.86)
= 100 - 52.53
mass of oxygen in 100 grams saltpeter = 47.47 grams
Now, we can use cross multiplication to find the mass of oxygen in 328 grams saltpeter as follows:
mass of oxygen = (328 x 47.47) / 100 = 155.7016 grams
The answer is d. extrusive.
The other term for it is <em>igneous rock</em>. Igneous rock is made in lava, and another term for igneous rock is extrusive rock.
have a great day! Brainliest is greatly appreciated, and please let me know if you need help with anything else ;)