Answer:
Step-by-step explanation:
To find the number of different ways she can stack 3 of them in a tower, we need to use the formula:

n = 4
k = 3





Answer:
0.3
30%
30/100 is the same as 60/200, both the numerator and denominator have been doubled.
Answer:
Quadratic polynomial is x^2 - x - 20
Answer:
64 degrees.
Step-by-step explanation:
This is because the arrow that is not horizontal is pointing to that number.