Express 15 gallons in liters (use 1 gallon is 3.79 liters).

What will be an ideal response?

Note: While gallons / liter is not in Table 4-3.3, it can be computed from information that is there using the conversion factors:
4 (qt / gal) 1 / 4 (gal / qt)
1.0566 (qt / L) 1 / 1.0556 (L / qt)
Combining = 4 (qt / gal) * 1 / 1.0566 (L / qt)
= 3.79 (L / gal) (rounded to 2 places)
For the current problem, the pair of reciprocal conversion factors are: 3.79 (L / gal) 1 / 3.79 (gal / L)
x (L) = 15 (gal) * 3.79 (L / gal) = 56.85 L