You have to add all the cost of the family had which is $6.84+$4.88+$8.32+$4.98
2.they would get $13.73 back
I got it by the $25.02 from the last one and add with tax which was 5% so I then in total of $26.271 and since this is money I rounded it up to $26.27. After I got that I subtracted the $40 since they use 2 $20. $40-$26.27=$13.73
3. I think it would be the estimate of 0.60 per ounce
I got that by dividing the total cost and the all the ounces which I got the estimate of 0.60
4. I think they should order the larger steaks than the smaller steaks to share since it would be for one family.
I am sorry if one of them are wrong but I hope this could help you.
to find how far it it will go you will need to find the circumference and times it by 2 to find the circumference the formula is 2*pi*radius so you would do 2*3.14*4 and that is 25.12 but since it is 2 revolutions you times 25.12 by 2