Answer:
What Table!?!?
Step-by-step explanation:
1. The probability that your mail is delivered before 2 pm is 0.9, so the probability that the mail is delivered at 2 pm or after 2 pm (so not before 2 pm) is 1-0.9=0.1.
Remark: 0.9=9/10=90/100=90%, and 0.1 is 10%
2. Probability of the mail being delivered before 2 pm for 2 consecutive days is

3. take a look at the picture attached, the tree diagram is another method we could use.
<h3>
Answer: A and B (first answer choice)</h3>
Explanation:
Both figures shown in A and B are triangular pyramids. The base is a triangle, and the lateral sides are also triangles. Another example would be rectangular pyramids where the base is a rectangle, and the lateral sides are triangles.
Choice C is ruled out because cones aren't considered pyramids.
Choice D is a combination of a rectangular prism, and a rectangular pyramid stacked on top, so it's not purely a pyramid only. We can rule out choice D.
B1 to H1, B3 to H2, B2 to H3.