Answer:
O is the center of the circle with radius IE(=ID=EF)
Step-by-step explanation:
Join all 3 points D, E, F, forming the triangle DEF.
Let the midpoint of EF be M and the midpoint of ED be N. (first picture)
Join point I to E, D and F.
Since IN is both an altitude and median to triangle EID, then triangle EID is an isosceles triangle, and IE=ID
similarly, we see that IE=IF.
conclusion: IE=ID=EF.
Answer:
10
Step-by-step explanation:
(-15+45)/3=10
Answer:
option A, C and D
Step-by-step explanation:
Each relation is a function if each input has only one output
{a, 1), (6, 1), (C, 1)
This relation is a function because each input has only one output
{a, a),(a, b),(a, c)}
This relation is not a function because input 'a' has only three output
{(1, a), (2, a),(3, a)}
This relation is a function because each input has only one output
{a, a), (b, b), (C, c)}
This relation is a function because each input has only one output
The answer is C: systematic sampling