Answer:
a spider has 4 pairs of legs, since they have 8 legs
The Fish does not give off Carbon Dioxide
Answer:
A. 
B. 
C. 
D. 
Explanation:
Hello.
In this case, we must compute the final concentration in all the cases so we solve for it in the given equation:

Thus, we proceed as follows:
A. Here, the final diluted solution includes the 300 μL of the 5 mg/ml-BSA and the 700 μL of TBS.

B. Here, the final diluted solution includes the 50 μL of the 1.5 mg/ml-BSA, the 450 μL of water and the 500 μL of TBS.

C. Here, the final diluted solution includes the 10 μL of the 1 mg/ml-BSA and the 990 μL of TBS.

D. Here, the final diluted solution includes the 10 μL of the 0.1 mg/ml-BSA and the 990 μL of TBS.

Best regards.
The measles virus and rubella virus are two separate viruses. They have different DNA and RNA structures, and the vaccination for the measles virus only "knows" how to attach itself to measles and destroy the virus. It doesn't know how to attach itself to the rubella virus to destroy it, as the vaccination is needed to inform it how to.
The advantage of vaccinating a large amount of the population is that it reduces the chance someone will catch sickness by a great amount, and can possibly eradicate the virus.