Answer:
H. 150
Step-by-step explanation:
Permutations formula:
The number of possible permutations of x elements from a set of n elements is given by the following formula:
[tex]P_{(n,x)} = \frac{n!}{(n-x)!}[/tex]
In how many ways can the contractors be chosen?
One pumbling(from a set of 15)
One electrical(from a set of 10)
So
[tex]P_{(15,1)}*P_{(10,1)} = \frac{15!}{(15-1)!}*\frac{10!}{(10-1)!} = 15*10 = 150[/tex]
So the correct answer is:
H. 150