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.
<span>How much of the Earth’s water is usable as a freshwater resource?
3%</span>
Answer:
Explanation:
Preparation of competent cells -
Transformation
recovery
plating
Answer:
the grass grew taller and the hawk population declined
Explanation:
have a good day
all the thymine pairs with adenine, therefore there is the same number of adenine and thymine bases and the same percentage
so we have 28%thymine and 28% adenine
100-28-28=44% left
this 44% is guanine and cytosine. All of the guanine pairs with cytosine and all of the cytosine pairs with guanine so we have 44/2=22% cytosine and guanine
composition:
28%adenine
28%thymine
22%guanine
22%cytosine