Please help I have a test tomorrow

I need explanation with D on both of these​

After the seventh month of a 12-month loan: the numerator is: {(n + 11) + (n + 10) + (n + 9) + (n + 8) + (n + 7) + (n + 6) + (n + 5)} = , and the denominator is: {(n) + (n + 1) + + (n + 11)} = . therefore, the fraction is numerator/denominator (to the nearest tenth) = %

Let hh represent the number of hummingbirds and ss represent the number of sunbirds that must pollinate the colony so it can survive until next year. 6h+4s > 746h+4s> 74 this year, 88 hummingbirds pollinated the colony. what is the least number of sunbirds that must pollinate the colony to ensure that it will survive until next year?

Determine if the following statement is true or false. the normal curve is symmetric about its​ mean, mu. choose the best answer below. a. the statement is false. the normal curve is not symmetric about its​ mean, because the mean is the balancing point of the graph of the distribution. the median is the point where​ 50% of the area under the distribution is to the left and​ 50% to the right.​ therefore, the normal curve could only be symmetric about its​ median, not about its mean. b. the statement is true. the normal curve is a symmetric distribution with one​ peak, which means the​ mean, median, and mode are all equal.​ therefore, the normal curve is symmetric about the​ mean, mu. c. the statement is false. the mean is the balancing point for the graph of a​ distribution, and​ therefore, it is impossible for any distribution to be symmetric about the mean. d. the statement is true. the mean is the balancing point for the graph of a​ distribution, and​ therefore, all distributions are symmetric about the mean.