The answer is B. Hope you get it.
Concept:
A <em>function f </em>from a set A to a set Y is a rule that assigns a unique element f(x) ∈ Y to each element x ∈A.
Points to remember:
1) There is no repetition in the domain of function.
2) Yo can use a 'vertical line test: A function f can have only one value f(x) for each x in its domain, so no vertical line can intersect the graph of a function more than once' to check that whether the given relation is a function.
Now, apply the above two points.
a) x²+y² = 9 , This is the equation of a circle so vertical line intersects the graph at two points, Given relation is not a function.
b) {(4, 2), (4, –2), (9, 3), (9, –3)}, repetition in Domain(4 occurs two times in domain and then 9 occurs two times) so Given relation is not a function.
c) x = 4 , this is a vertical line so repetition in Domain occurs (x=4 infinite values of y occcur) so Given relation is not a function.
d) 2x + y = 5 , equation of a line so according to vertical line test there is no repetition in domain so Given relation is a function.
The mean is 10,724.28.
Explanation:
The mean is all of the values divided by the number of values there are.
So what you have to do is add all of the numbers and divide it by the amount of numbers there are.
10,150+10,211+10,424+10,769+10,884+11,155+11,477= 75,070.
Since there are 7 numbers, divide 75,070/7 and you get your mean, which is 10,724.28 rounded.
Answer:
(4²πx2) + (8π x 4) = 201.061... OR 64π