Genetic mutations increase variety by adding uniqueness to the world. Genetic mutations can come in all shapes and sizes based on the chromosomes in cells. Perhaps someone was born with one blue eye and one green eye, or perhaps they have hair a certain, unusual color. Genetic mutations add variety to the world by making sure everyone isn't the same!!
B. One
because an independent variable is something you change. So in a scientific experiment you only change one thing. If you happen to change more than one thing then the test becomes unfair therefore you should repeat and make sure that only one thing is changed this time.
Answer:
Is the benefit worth the cost?
Explanation:
Environmental policies application has to lead to some economic cost.
When coming up with this policies, the effect that this policies shall have towards environmental protection shall be considered.
The cost and economic effect that this policies shall cause should also be looked at.
If a policy causes insignificant change towards environmental protection and at the same time the costs are too high, then the policy should be dropped.
If a policy has got significant impact and costs less, the it should be taken.
A star’s life expectancy depends on its mass. Generally, the more massive the star, the faster it burns up its fuel supply, and the shorter its life. The most massive stars can burn out and explode in a supernova after only a few million years of fusion. A star with a mass like the Sun, on the other hand, can continue fusing hydrogen for about 10 billion years. And if the star is very small, with a mass only a tenth that of the Sun, it can keep fusing hydrogen for up to a trillion years, longer than the current age of the universe.