Donna plans to save for a vacation to Costa Rica in 18 months. She will be putting the money into a short-term investment account earning 4% annually. How much will Donna have to put away at the beginning of each month if the total package cost for the trip is $3,500?

		a. $170.34.
		b. $188.37.
		c. $212.69.
		d. $246.73.