I'm lil stuck on sentence 2 and sentence : 4 can someone me with the answer

I think the answer to 2b is 0.9 and 2c is 0.1 
for question for 4 is 25 + 3 = 28. 28 inches were cut off. 
for question 4a 6.03 / 4.5 = 1.34. 1.34 per pound 
for the last question 0.4 x 12 = 4.8 so 4.8-4.6 = 0.2 
4.6/12= 0.38 so 0.40-0.38 = $0.02 saved per can