Answer:
a) An event with probability 0 is said to be impossible
b) An event with probability 1 is said to be certain
c) The probability of getting a head when flipping an unbiased coin is shown by the letter A
Step-by-step explanation:
a) If something has a 0 on a probability scale, it will never happen. The word used to describe this outcome is impossible.
b) If something has a 1 on a probability scale, it will always happen. The word used to describe this outcome is certain.
c) The probability of getting a head on an unbiased coin is 
or 
. This means that we are looking for the letter that is in the exact center of 0 and 1. It can be seen that A is in the dead center of these two numbers, so this is our answer.
Answer:
Coldest day on record = -20°C
Step-by-step explanation:
Given:
Yesterday temperature = -4°C
Coldest day on record = 5 times than yesterday
Find:
Coldest day on record
Computation:
Coldest day on record = 5 × Yesterday temperature
Coldest day on record = 5 × (-4)
Coldest day on record = -20°C
The cosine of an angle is the x-coordinate of the point where its terminal ray intersects the unit circle. So, we can draw a line at x=-1/2 and see where it intersects the unit circle. That will tell us possible values of θ/2.
We find that vertical line intersects the unit circle at points where the rays make an angle of ±120° with the positive x-axis. If you consider only positive angles, these angles are 120° = 2π/3 radians, or 240° = 4π/3 radians. Since these are values of θ/2, the corresponding values of θ are double these values.
a) The cosine values repeat every 2π, so the general form of the smallest angle will be
... θ = 2(2π/3 + 2kπ) = 4π/3 + 4kπ
b) Similarly, the values repeat for the larger angle every 2π, so the general form of that is
... θ = 2(4π/3 + 2kπ) = 8π/3 + 4kπ
c) Using these expressions with k=0, 1, 2, we get
... θ = {4π/3, 8π/3, 16π/3, 20π/3, 28π/3, 32π/3}
