#### Answer

(a) The center will need 12.5 quarts of milk per week.
(b) 4 gallon containers will be needed for one week.

#### Work Step by Step

Compute how many cups of milk are needed, then convert to quarts and gallons.
Multiply amount per toddler by number of toddlers by number of days.
$\frac{2}{3}\times15\times5=\frac{30}{3}\times5=10\times5=50$
cups of milk are needed each week.
Convert to quarts.
$50 c\times\frac{1 qt}{4 c} = \frac{50}{4} qt = 12.5 qt$
Convert to gallons.
$12.5 qt\times\frac{1 gal}{4 qt}=\frac{12.5}{4} gal=3.125 gal$