A isn't true because 513 is at least divisible by 3, so it's not a prime number.
C isn't true because all whole numbers are either prime or composite.
D isn't true because it is neither a imaginary number, fraction, decimal, or unreal number, so therefore it must be a whole number.
B is true, because it is able to be divided by numbers other than one and itself.
Answer:The base of the ladder should be placed so that it is one foot away from the building for every four feet of hight to where the ladder rests against the building. This is known as the 4 to 1 rule.
Step-by-step explanation:
