Answer:
12 for 40 cents is a better deal.
Step-by-step explanation: 35divided by 10 is 3.5 and 12 divided by 40 is 3.333... therefore for just one card it is cheaper but you are getting more cards anyways.
Answer:
The mass of the pipe is 
Step-by-step explanation:
step 1
Find the volume of the steel pipe
The volume is equal to the area of outside circle minus the area of inside circle, multiplied by the length of the pipe
so
![V=\pi [r2^{2}-r1^{2}]L](https://tex.z-dn.net/?f=V%3D%5Cpi%20%5Br2%5E%7B2%7D-r1%5E%7B2%7D%5DL)
we have
---> the radius is half the diameter
---> the radius is half the diameter


substitute
=59.66\ cm^{3}](https://tex.z-dn.net/?f=V%3D%283.14%29%5B1%5E%7B2%7D-0.9%5E%7B2%7D%5D%28100%29%3D59.66%5C%20cm%5E%7B3%7D)
step 2
Find the mass
The mass is equal to the density multiplied by the volume
so

Trip G at 1000 miles earning 5 points a mile plus an extra 20 for every 500