ILL GIVE BRAINLIEST PLZ HELP. Atoms of carbon-14 are radioactive. They decay into atoms of the element nitrogen. Suppose that a sample of rock is taken from a fossil. The sample has 500 atoms of carbon-14 and 1500 atoms of nitrogen. If carbon-14 has a half-life of 5700 years, how old is the fossil? 5700 years old 11,400 years old 17,100 years old 2850 years old

11,400 years old

Explanation:

The total  number of atoms present at the beginning = number of C-14 + number of N-14 atoms.

Hence;

1500 + 500 = 2000 atoms = No

At time t, N = 500 atoms of C-14 remains

Since the half life of C-14 (t1/2) = 5700 years

N/No = (1/2)^t/t1/2

500/2000 =  (1/2)^t/5700

1/4 = (1/2)^t/5700

(1/2)^2 =(1/2)^t/5700

2 = t/5700

t = 2 * 5700

t = 11,400 years old

the answers are as following:

1. c. double helix, nucleosome, coil, supercoil, chromosome

2. b. g2 phase, preparation for mitosis

3. d. interphase consists of the g1, s, and g2 phases

4. c. metaphase

5. a. chromosomes are duplicated before cell division so that each new daughter cell has a complete set

hypoxemia refers to a below usual concentration of oxygen in the blood, mainly in the arteries. hypoxemia is an indication of an issue associated with circulation or breathing and may lead to various symptoms like shortness of breath.  

the condition is identified by determining the level of oxygen in the blood sample obtained from an artery. it can also be predicted by determining the oxygen saturation of the blood with the application of a pulse oximeter.  

the normal arterial oxygen is about 75 to 100 mm hg. the values underneath 60 mm hg is generally considered with the requirement for supplemental oxygen. the normal pulse oximeter readings generally range between 95 to 100 percent. the values under 90 percent are regarded as low.  

in the given case, the oxygen saturation is measured at 93 percent, hence, there is no need to administer oxygen, that is, one should withhold oxygen.