Answer:
Option D is the correct answer
Explanation:
There are three hydrogen bonds formed between Guanine and Cytosine base.
The first hydrogen bond is formed between the oxygen atom on Carbon-6 (C-6) of guanine, and one of the hydrogen atoms attached to the Nitrogen atom (i.e the one of the hydrogen atoms in the amino group) on the Carbon-4 (C-4)of the cytosine base.
The second hydrogen bond is formed between the hydrogen atom on Nitrogen-1 (N-1) of the guanine base and Nitrogen-3 (N-3) of the cytosine base.
The third hydrogen bond exist between one of the hydrogen atoms in the amino group attached to the second Carbon (C-2) of the guanine base, and the oxygen atom attached to the second Carbon (C-2) of the cytosine base.
Answer:
The correct answer is the imperial system.
Explanation:
Only three countries in the world, that is, the United States, Myanmar, and Liberia use the imperial system. These include measurements in the form of inches, ounces, Fahrenheit, and feet. In the imperial system, the distances, height, weight, or area measurements are used eventually that traced back to everyday items or parts of the body.
In comparison to other metric systems, the units used in the imperial system are not further differentiated easily into parts of hundreds or thousands, and are thus, regarded of less use in comparison to other metric systems by some. The real follower of the imperial system at present in the world is the United States.
The mole ratio is 4 NO2 to 3 O2; 4:3
From ideal gas equation that is PV=nRT
n(number of moles)=PV/RT
P=760 torr
V=4.50L
R(gas constant =62.363667torr/l/mol
T=273 +273=298k
n is therefore (760torr x4.50L) /62.36367 torr/L/mol x298k =0.184moles
the molar mass of NO2 is 46 therefore density= 0.184 x 46=8.464g/l
Scientists use carbon-14 to date ancient fossils.
Plants and animals absorb carbon-14 produced by cosmic rays. The ratio of C-14 to C-12 is constant when they are alive.
When they die, the C-14 decays to C-12, and the ratio changes.
Carbon-14 has a half-life of 5730 years. Thus, the object loses half its C-14 every 5730 years.
Scientists can use the C-14 to C-12 ratio to date fossils up to 70 000 years old.
