Answer:
Plumber: 13 hours
Plumbing service: 10
Step-by-step explanation:
What you have to find is LCM(least common multiple in order to find the lcm all you have to do is list all the multiples and find their common multiple.
The value of the number 2.4x10⁻⁴ in the standard notation is 0.00024.
<h3>What are Scientific notations?</h3>
The way through which a very small or a very large number can be written in shorthand. In scientific notations when a number between 1 and 10s is multiplied by a power of 10.
For example, 6,500,000,000,000 can be written as 6.5×10¹².
As the value of the scientific notation is given 2.4x10⁻⁴, therefore, for bringing it in the standard form we need to shift the decimal to the left by four digits. So,

Hence, the value of the number 2.4x10⁻⁴ in the standard notation is 0.00024.
Learn more about Scientific notation:
brainly.com/question/1740231
I am not sure about this. I am sure that 3 has atleast 1.