Answer: A substance is matter which has a specific composition and specific properties. Every pure element is a substance. Every pure compound is a substance. Examples of substances: Iron is an element and hence is also a substance.
Explanation:
answer:
our sun will never become a neutron star.
explanation:
- neutron stars are born from suns that are 10-20 times the size of ours.
- in 5 billion years our sun will become a red giant and then eventually a cold white dwarf which is similar to a neutron star, just much larger and much less dense.
Blood type O can be given to anyone.
Answer:
Equal amounts of DNA contain equal proportions of nitrogenous bases.
Explanation:
According to Chargaff's rule, the nitrogenous base pairs (Purines and pyrimidines) have an equal ratio (1:1) in the DNA of all the organisms. More precisely, the amount of adenine is equal to thymine and the amount of guanine is equal to cytosine in the DNA of all the organism. A-T base pair has two H-bonds while G-C base pair has three H-bonds.
The advantage of small and large reserves is that it only
requires small labor and it can also serve a city and a town. The only disadvantage
of the small and large reserves is that it is quite expensive despite of its
usefulness.
