There is no element with one valence electron and six energy levels. Only two valence electrons and six energy levels.
Answer:
Calcium
Explanation:
A: Calcium is a group 2 element with two valence electrons. Therefore, it is very reactive and gives up electrons in chemical reactions. It is likely to react with an element with six valence electrons that “wants” to gain two electrons. This would be an element in group 6, such as oxygen.
Answer: For decreased chances of rejection
Explanation:
The three higly polymorphic MHC 1 genes in human beings are HLA-A, HLA-B and HLA-C.
These determine the compatibility of the organ or tissue in the recipient's body each by the help of many alleles that segregates in a population.
There are very less chances that a random chosen donor will match the a recipient six allele genotype.
This is the reason parent may be the best donor for organ transplantation or tissue transplantation.
I believe the answer is Integumentary, Hope this helps ")
Answer:
Estimated size is 1600
Explanation:
Given data:
Size of lake is 250 hectares
Total number of trout who netted is 400
Total number of trout in next week is 200
Total number of trout having fin clip 50
estimation population size is estimated by mark rupture as follow
Estimated population size 
Estimated size
Estimated size is 1600
Answer:
Temperature
Explanation:
catalyst have specify temperature range for their efficiency