It's been a while since I've studied this, but my answers would be:
13. 5730 years. The half-life of a substance is the amount of time it takes for half of it to decay, and, according to the graph, half of the substance remained at 5730 years.
14. 10740 years. According to the graph, only 25% of the carbon remained after 10740 years.
15. 15 atoms. According to the graph, only 12.5% of the carbon remained after 16110 years. 12.5% of 120 atoms is 15 atoms.
16. 1600 atoms. According to the graph, if a sample of carbon is 10740 years old, only 25% of it remains. To find the original amount, multiply the current amount by (100% / 25%), which equals 4. So, 4. 400 atoms * 4 = 1600 atoms is the original amount.
<span>a) All the 26m should be used to bent into a square to maximize the total area (= 42.25 m2)
b) 1.4136m should be bent into a square and the rest (= 24.586m) should be bent into an equilateral triangle to minimize the total area (= 29.0835m2)</span>
Fertilizer application can be detrimental when there is overapplication. The excess nutrients are washed away by runoff after precipitation. These nutrients end up in water bodies and cause algal blooms. Algal blooms asphyxiate aquatic life hence causing a drastic reduction in aquatic populations.
