Any of the tens i think (10=60, 20+50, etc.), but i am not too sure what is implied by regrouping. if i am right in thinking this only means "carrying" a digit after adding, then anything that adds up to 70 would work unless the sum of the digits in the ones place exceeded 9.
It would be -7f degrees because -14-7 would equal -7
Since a triangles angles add up to 180 you would add the other sides and then
180-161=19
So angle 1 is 19 degrees
The first part cannot be answered here without the diagram. However, I can tell you that the model he's building is 1/10 the size of the actual car. That means every measurement on the car is divided by 10 to get the model measurement.
The radius of the car wheel is 27 inches, so the diameter is 54 inches. Using what we know about the model, the correct proportions for the model wheel diameters would be 54 / 10, or 5.4, inches. Therefore, wheels with a diameter of 6 inches would not be in proportion with the model.