What to do to find out what x stands for?

Acable company wants to provide cell phone service for residents on an island. the function for the cost of laying the cable from the island to the mainland is c(x)= 6.500 square root x2+4, where x represents the length of the cable in feet. what are the domain and range of the function? a) domain: all real numbers range: all real numbers greater than or equal to 17,000 b) domain: all real numbers greater than or equal to 0 range: all real numbers greater than or equal to 17,000 c) domain: all real numbers greater than or equal to 0 range: all real numbers greater than or equal to 13,000 d) domain: all real numbers greater than or equal to 13,000 range: all real numbers greater than or equal to 0

Eight people were asked what the balance of their savings account at the beginning of the month was and how much it increased or decreased by the end of the month. create a scatter plot that represents the data that is shown in the table. the x-axis represents the beginning balance in thousands of dollars and the y-axis represents the change in the savings account in hundreds of dollars. name beginning balance (in thousands of dollars) change in savings account (in hundreds of dollars) jimmy 5 3 kendra 4 7 carlos 5 4 yolanda 3 1 shawn 2 5 laura 3 2 andy 5 6 georgia 4 3

At the olympic games, many events have several rounds of competition. one of these events is the men's 100-meter backstroke. the upper dot plot shows the times (in seconds) of the top 8 finishers in the final round of the 2012 olympics. the lower dot plot shows the times of the same 8 swimmers, but in the semifinal round. which pieces of information can be gathered from these dot plots? (remember that lower swim times are faster.) choose all answers that apply: a: the swimmers had faster times on average in the final round. b: the times in the final round vary noticeably more than the times in the semifinal round. c: none of the above.