Anew computer has a model number, a part number, and a serial number. the model number is assigned by the manufacturer to identify the type of computer. the part number identifies one part of the smaller components that make up the computer. the serial number is unique to each computer produced and identifies it. which relation is a function?

(serial number, model number)

That's a function mapping each serial number to its model number.

 (part number, serial number)

That's not a function; the same part number is in computers with different serial numbers

 (model number, part number)

That one's a bit confusing.  Normally a given model would have more than one part number inside so this isn't a function.  But here the description says there's only one part number for each model, so that would be a function.

(model number, serial number)

Not a function, more than one serial number for a given model number.

                                                      hope it helps

13

step-by-step explanation:

distance formula is d=√(x2-x1)^2   +   (y2-y1)^2

step-by-step explanation:

12: 00 p.m. to 7: 00 p.m. is a total of 7 hours.

4: 00 p.m. to 7: 00 p.m. is a total of 3 hours.

this means that from 4: 00 p.m to 7: 00 p.m. this represents 3/7 of what was lost from 12: 00 p.m. to 7: 00 p.m.

after knowing this, after doing 11,600 - 6,800 = 4,800

4,800 represents 3/7 of what was lost for 7 hours.

we then divide 4,800 by 3 which gets 1,600.

because we know that 1,600 represents 1/7 of how much water was lost, we just have to multiply by 7, which gets 11,200.   after adding 11,200 to how much water was left at 7: 00 p.m. which was 6,800. 11,200 + 6,800 = 18,000

this means that the pool originally had 18,000 gallons in the pool.

you can also check your work by doing 18,000 - 4(1600), which becomes           1800 - 6400 which gets you 11,600.