For f(x - 3.5) the answer is that f(x) is translated 3.5 units right
You can figure that out by thinking that for x = 3.5 (which is 3.5 units to the right of x = 0, f(3.5 - 3.5) is the same that f(0), ... for x = 10.5 (which is 3.5 units to the right of x = 7, f(10.5 - 3.5) = f(7) ... and so for every value of x.
For 3.5 f(x) the answer is that f(x) is vertically stretched by a factor of 3.5 which you figure out from a table like this:
f(x) 3.5 f(x)
0 0
1 3.5
2 7
10 35
And from that you can see the 3.5 f(x) is horizontally compressed and vertically stretched respect to f(x).
The full steel bead tire would weigh 1.5432358353 pounds, or about 1.8. The lighter wheel weighs 1.5432358353 pounds, or about 1.5. Together they weigh 3.086471671, or about 3.1 pounds.