<h2>1)</h2>

This must be true for some value of x, since we have a quantity squared yielding a positive number, and since the equation is of second degree,there must exist 2 real roots.

<h2>2)</h2>
Well he started off correct to the point of completing the square.

To solve this question, you just need to count all the probability of the options.
The probability that a pitch not over the plate is a strike is zero. So, P(A | D) = 0.
True. It is 0/0+20= 0
The probability that a pitch not over the plate is a ball is 1. So, P(B | D) = 1.
True, it is 20/20+0= 1
The probability that a pitch over the plate is a strike is 10:15. So, ...
Incomplete but it sounds to be true. It should be 10/10+5= 10/15 = 2/3
The probability that a pitch over the plate is a ball is 5:10. So, P(B | C) = 0.5.
Let

denote the random variable for the weight of a swan. Then each swan in the sample of 36 selected by the farmer can be assigned a weight denoted by

, each independently and identically distributed with distribution

.
You want to find

Note that the left side is 36 times the average of the weights of the swans in the sample, i.e. the probability above is equivalent to

Recall that if

, then the sampling distribution

with

being the size of the sample.
Transforming to the standard normal distribution, you have

so that in this case,

and the probability is equivalent to

Sorry I have to go to baseball bye