Farmula to calculate perimeter of rectangle

What is the length of the segment joining the points at (4,5) and (6,-2) round to the nearest tenth if necessary

Is the number 128.439 a rational number

The water company charges a residential customer $41 for the first 3,000 gallons of water used and $1 for every 200 gallons used over 3000 gallons. if the water bill was $58 how many gallons of water were usedanswersa 3400 gallonsb 6000 gallonsc 6400 gallons d 7000 gallons