A beam of light (travelling at the speed of light) would take 65 years to go and 65 years to come back from aldebaran, i.e. 130 years. You can send and receive a radio message (travelling at the speed of light, being electromagnetic radiation) taking so 130 years.
Answer:

Step-by-step explanation:
The formula of a midpoint between two points A(x₁, y₁) and B(x₂, y₂):

We have the points (3, 17) and (-14, -8).
Substitute:

Answer:
1) 120
2) E (Z) = 12 and Variance of Z = 90
a) 5 liters
Step-by-step explanation:
1. We can find this by suing combinations.
Here n= 10 and r= 3 so n C r
= 10 C 3= 120
2. E(X) = 8 and E(Y) = 3
Z = 2X - 3Y +5
E(Z ) = 2 E (X) - 3(E)(Y) +5 ( applying property for mean)
= 2(8) - 3(3)+ 5 = 16+5-9= 21-9= 12
V(X) = 9 and V(Y) = 6.
V(Z) = E(Z )²- V(X) *V(Y) (applying property for Variance for two variables )
= 144- 54= 90
3. 55 liters contain adulterated milk in 7: 4.
So it contains 4/ 11*55= 20 liters of water
But we want to make it a ratio of 7:6
the water will be 6/13 *55= 25.38 when rounded gives 25 liters of water
So 25- 20 = 5 liters must be added to make it a ratio of 7:6
Answer:
C
Step-by-step explanation:
AP Classroom says so
The first answer is correct, if you go back by 5% each year you will see that.