Answer:
$2070
Step-by-step explanation:


I'd say the 3rd one. I haven't done this stuff in 2 years ... me forgot. But if it's not right, then the 1st one!
I want you to know you're smart and you can do this! Good luck!
Answer:
No Solution
Step-by-step explanation:

Expand:


Add 5 to both sides:


Subtract 4x from both sides:


No solution as this is false.
There is a 6% decrease as 639.20 divided 680 is 0.94. Meaning 6% decrease.
Answer:
A recent report estimated that 25% of all college students in the United States have a sexually transmitted disease (STD). The director of the campus health center believes that the proportion of students with STDs is higher at their campus.
According to the American Heart Association guidelines, the daily maximum amount of sugar a teenager should have is 4 teaspoons. The parents of a local high school have expressed concerns that the average daily sugar intake of their students is higher than these guidelines and have been pressuring school officials to limit unhealthy snack and beverage choices offered in the cafeteria and student store.
Step-by-step explanation:
The first two researches involve the single sample compared to mean of population.
The 3rd and 4th research involves comparing samples of men and women that is two individual groups.