1/3 for the first one, and 3/4 for the second one :)
Answer: 0.0688
Step-by-step explanation:
Given : Current research indicates that the distribution of the life expectancies of a certain protozoan is normal with a mean of 43 days and a standard deviation of 10.1 days.
i.e.
and 
Let x represents the life expectancies of a certain protozoan.
Sample size : n= 25
The probability that a simple random sample of 25 protozoa will have a mean life expectancy of 46 or more days. :-

[using z-value table]
Hence, the required probability = 0.0688
To round to the nearest tenth place you are going to round the last two digits of that, you should get 519.7