The controlled variable is what he eats, the dependent variable is his weight.
a word of advice for your next ask, try to use better grammar and punctuation because this was kinda hard to follow.
Answer:
Really sorry I don't know answer
The reaction equation:
2H₂O + 2Na₂O₂ → 4NaOH + O₂
Moles of sodium peroxide = 10 / 78 = 0.128
Moles of oxygen released = 0.128 / 2 = 0.064 mol
Mass of oxygen = 0.064 x 32
Mass of oxygen = 2.05 grams
Answer:
12.5%
Explanation:
Initial percentage of carbon 14 = 100%
Final percentage = ?
Time passed = 17.1 * 1000 years = 17100 years
Half life of carbon 14 = 5,730 years.
So how many Half lives are in 17100 years?
Number of Half lives = Time passed / Half life = 3.18 ≈ 3
First Half life;
100% --> 50%
Second Half life;
50% --> 25%
Third Half life ;
25% --> 12.5%