Plane: a flat surface that extends infinitely and has no depth, it has length and width.
Perpendicular Lines: two lines that intersect at angles.
Parallel Lines: two lines that lie within the same plane and never intersect.
Circle: a set of all points in a plane that are a given distance from a point
Angle: a figure consisting of two rays with a common endpoint.
Hope this helps!
The elements found in greatest abundance in the Earth include oxygen, silicon, aluminum, iron and calcium; these substances also make up the bulk of the moon. Although the moon is a<span>n airless world, it has large amounts of oxygen in the form of solid chemical compounds.</span>
Answer:
a) 
b) 
Step-by-step explanation:
Conditional probability is the probability of one event occurring with some relationship to one or more other events.
The total probability rule (or the Law of Total Probability) breaks up probability calculations into distinct parts. P(AUB)=P(A)+P(B)-P(A and B)
The general multiplication rule formula is: P(A ∩ B) = P(A) P(B|A)=P(B)P(A|B)
We have the following probabilities:



Part a
We can use this multiplication rule:

For this part we want this probability:

And if we replace we got:

Part b
For this part we want the probability of one event in last year OR one event on the current year, so we can use the probability addition of events:

And for our case we have:

