With math and best gets brainliest and remember to show work.

1. If a section of carpet is $140 for 18 square feet, then all we have to do is divide to find the amount per square foot.

140 / 18 = 7.777777...

The carpet is approximately $7.78 per square foot.

2. If a certain type of grain costs $2.99 for 14 lbs, then again, we just need to divide to find the amount per pound.

2.99 / 14 = 0.2135714...

The grain costs approximately $0.21 per pound.

3. To find the better deal, we just need to divide both and find which one costs less overall

56 / 25 = 2.24

32.05 / 15 = 2.136666...

The second option costs approximately 10 cents less than the first, so that would be the better deal.

4. Again, we just need to divide to find the better deal.

160 / 5 = 32

315 / 9 = 35

The first item costs $3 less per gram, so that would be the better deal.
Hope that helped =)