it is trapped beneath non porous rocks
Answer:

Explanation:
It is given that
B is the dominant allele which represents the black color
and b is the recessive allele which represents the white fur.
B being dominant will result into black color fur for genotype "Bb"
Given -
Frequency of black fur allele (p) is 
As per Hardy Weinberg's first law of equilibrium

Substituting the value of p in above equation, we get -

q represents the frequency for white fur allele
Frequency of white fur phenotype is

Frequency of homozygous black fur phenotype (BB) is

As per Hardy Weinberg's second law of equilibrium -

Combined frequency of homozygous and heterozygous black fur phenotype is

Answer;
Iodine
A diffuse, nontoxic goiter is usually due to a lack of Iodine in the diet.
Explanation;
-A diffuse non-toxic goiter is an enlargement of the thyroid gland without nodularity. It occurs in an endemic and sporadic distribution. It does not result from an inflammatory or neoplastic process and is not associated with abnormal thyroid function.
-Simple nontoxic goiter, which may be diffuse or nodular, is noncancerous hypertrophy of the thyroid without hyperthyroidism, hypothyroidism, or inflammation. Except in severe iodine deficiency, thyroid function is normal and patients are asymptomatic except for an obviously enlarged, non tender thyroid.
But my guess its a oxygen? Or carbon dioxide?
Amino acids speed up or slow down the chemical reactions of organisms