Charcoal from the dwelling level of the Lascaux Cave in France gives an average count of 0.97 disintegrations of C-14 per minute per gram of sample. Living wood gives 6.68 disintegrations per minute per gram. Estimate the date of occupation and hence the probable date of the wall painting in the Lascaux Cave. (Half-life of C-14 is 5568 years)

15502 years

Explanation:

From;

0.693/t1/2 = 2.303/t log [Ao]/[A]

Where;

t1/2 = half life of C-14

t = time taken

[Ao] = count rate of living sample

[A] = count rate of the charcoal under study.

0.693/5568 = 2.303/t log (6.68/ 0.97)

1.245 * 10^-4 = 2.303/t log (6.887)

1.245 * 10^-4  = 1.92998/t

t = 1.92998/1.245 * 10^-4

t = 15502 years

plants need sunlight, water, and carbon dioxide to make food. plants use the raw materials of water, nutrients they absorb from soil, and carbon dioxide to make sugars the plant can use. energy from the sun and chlorophyll are also needed.