35% of freshman are enrolled in American History, 40% of freshman are enrolled in European History, and 25% of freshman are enrolled in Ancient History. What is the total percentage of freshman in American and European History?

Describe in detail how you would construct a 95% confidence interval for a set of 30 data points whose mean is 20 and population standard deviation is 3. be sure to show that you know the formula and how to plug into it. also, clearly state the margin of error.

Each month, a shopkeeper spends 5x + 14 dollars on rent and electricity. if he spends 3x−5 dollars on rent, how much does he spend on electricity? for which value(s) of x is the amount the shopkeeper spends on electricity less than $100? explain how you found the value(s).

If the discriminant if a quadratic equation is 4 which statement describes the roots?