Tuvalu consists of three reef islands and six true atolls. Its small, scattered group of atolls have poor soil and a total land area of only about 26 square kilometres (10 square miles) making it the fourth smallest country in the world. The islets that form the atolls are very low lying. Nanumanga, Niutao, Niulakita are reef islands and the six true atolls are Funafuti, Nanumea, Nui, Nukufetau, Nukulaelae and Vaitupu. Tuvalu's Exclusive Economic Zone (EEZ) covers an oceanic area of approximately 900,000 km2.

How many reef islands does the Tuvalu group have?