There is a rule:
One input(x-value) can only have one output(y-value) in order to be a function.
If one input has more than one output, it is not a function.
(This doesn't apply to outputs, one output can have more than one input and still be a function)
The 1st option is not a function because the inputs 9 and 10 have more than one output.
The 2nd option is not a function because the input 3 has more than one output.
The 3rd option is a function because each input only has one output.
The 4th option is not a function because the input 5 has more than one output.
Dana can type 90 words per minute.
Since, 1 minute =
hours
Therefore, number of words she can type = 
= 90×60
= 5400 words per hour
If she types
words in 'x' hours.
Number of words Dana types with the given speed in 'x' hours = Speed of typing × Time
= 
Therefore, 


hours
Therefore, Dana types
words in 48.15 hours.
Learn more,
brainly.com/question/621754
Answer:
90 in²
Step-by-step explanation:
The figure's area is that of four right triangles, each with legs of 6 in and 7.5 in. The area of each triangle is half the product of the leg lengths, so is ...
triangle area = (1/2)(6 in)(7.5 in)
Then the area of 4 of those triangles is ...
figure area = 4 · triangle area = 2(6 in)(7.5 in) = 90 in²
Answer:
b - 7 = the amount of money Cam has
Step-by-step explanation:
We don't know how much money ben has so we have to subtract 7 from <em>b</em> to find the amount of money Cam has.
Hope this helps!