Distribute the A to the B and the b, then the a to the B and the b. You should get four different possible combinations: AB Ab aB ab. These would then be used to set up one side of a punnett square, and the other parent's genotype would be set up the same, then put on the other side of the punnett square.
The correct answer is answer choice A, 'In predation the predator usually kills its prey, whereas in parasitism the parasite does not usually kill its host'. While parasites can occasionally kill their hosts, it is more beneficial for the parasite to keep its host alive so that it can continue surviving off of the nutrients it gathers. Answer choice B is incorrect because the prey in predator-prey relationships and the host in parasitism do not benefit. Answer choice C is incorrect because the host does not benefit in parasitism, and is often harmed by the parasite. Answer choice D is incorrect because a predator usually kills its prey, while a parasite usually does not kill its host.
Hope this helps!
Answer:The ratio of the concentrations of 
and 
when the buffer has a pH of 7.02 is 0.69
Explanation:
The dissociation constant for formic acid = 
Concentration of HA= 0.5 mM
Concentration of = 0.1 mM
pH = 6.16
First we have to calculate the value of 
.
Using Henderson Hesselbach equation :
![pH=pK_a+\log \frac{[A^-}{[HA]}](https://tex.z-dn.net/?f=pH%3DpK_a%2B%5Clog%20%5Cfrac%7B%5BA%5E-%7D%7B%5BHA%5D%7D)
Now put all the given values in this expression, we get:
![6.16=pK_a+\log (\frac{[0.1]}{0.5})](https://tex.z-dn.net/?f=6.16%3DpK_a%2B%5Clog%20%28%5Cfrac%7B%5B0.1%5D%7D%7B0.5%7D%29)
To calculate the ratio of the concentrations of and when the buffer has a pH of 7.02.
Using Henderson Hesselbach equation :
![7.02=6.86+\log \frac{[A^-]}{[HA]}](https://tex.z-dn.net/?f=7.02%3D6.86%2B%5Clog%20%5Cfrac%7B%5BA%5E-%5D%7D%7B%5BHA%5D%7D)
![\frac{[A^-]}{[HA]}=1.44](https://tex.z-dn.net/?f=%5Cfrac%7B%5BA%5E-%5D%7D%7B%5BHA%5D%7D%3D1.44)
![\frac{[HA]}{[A^-]}=0.69](https://tex.z-dn.net/?f=%5Cfrac%7B%5BHA%5D%7D%7B%5BA%5E-%5D%7D%3D0.69)
Thus the ratio of the concentrations of and when the buffer has a pH of 7.02 is 0.69
