Answer: D, 6km/hr.
Step-by-step explanation:
Heather can finish a 12-kilometer race in 2 hours, and now we have to find how many kilometers she can ride/run at in 1 hour.
How many hours can Heather run in 1 hour? To solve that, we can use the equation 12 ÷ 2.
12 ÷ 2 = 6.
Therefore, if Heather keeps her pace constant, then her rate will be 6km/hr, or D.
Consider such events:
A - slip with number 3 is chosen;
B - the sum of numbers is 4.
You have to count 
Use formula for conditional probability:

1. The event
consists in selecting two slips, first is 3 and second should be 1, because the sum is 4. The number of favorable outcomes is exactly 1 and the number of all possible outcomes is 5·4=20 (you have 5 ways to select 1st slip and 4 ways to select 2nd slip). Then the probability of event
is

2. The event
consists in selecting two slips with the sum 4. The number of favorable outcomes is exactly 2 (1st slip 3 and 2nd slip 1 or 1st slip 1 and 2nd slip 3) and the number of all possible outcomes is 5·4=20 (you have 5 ways to select 1st slip and 4 ways to select 2nd slip). Then the probability of event
is

3. Then

Answer: 
Number of trees that are grew more than 3 feet = 10 + 35 = 45
Number of trees that grew more than 3 feet and is more than 50 yards away = 35
P(3 feet and more than 50 yards) = 35/45 = 7/9
Answer: 7/9
9514 1404 393
Answer:
132°
Step-by-step explanation:
Name the vertex of each angle the same as the angle letter. Name the intersection of the "horizontal" and "vertical lines" point Q.
Angle ZXQ is vertical to ∠x, so is the same measure.
Angle YQX is the value that makes the sum of angles in triangle XYQ be 180°. That is ...
∠YQX = 180° -51° -57° = 72°
This is also the measure of its vertical angle in the other triangle. Angle z is the sum of that vertical angle and 60°, so we have ...
∠z = 72° +60°
∠z = 132°
_____
<em>Additional comment</em>
The relations we used are ...
- vertical angles are congruent
- sum of angles in a triangle is 180°
- an exterior angle is equal to the sum of the remote interior angles
Answer:
Step-by-step explanation:

(x + 7)° = (15 + 7)° = 22°
(4x + 8)° = (4*15 + 8)° = (60 + 8)° = 68°