A survey asks a random sample of 2500 adults in Ohio if they support an increase in the state sales tax from 5.25% to 5.50%, with the additional revenue going to education. Let X denote the number in the sample that say they support the increase. Suppose that 30% of all adults in Ohio support the increase.

1. The mean of X is

a. 30.

b. 525.

c. 750.

d. 1750.

2. The standard deviation of X is

a. 22.91.

b. 27.39.

c. 5255.

d. 750.

3. The probability that X is at least 800 is

a. less than 0.0001.

b. about 0.015.

c. 0.025.

d. 0.05.