Input: Article: Mechanical pulping yields almost a tonne of pulp per tonne of dry wood used, which is why mechanical pulps are sometimes referred to as "high yield" pulps. With almost twice the yield as chemical pulping, mechanical pulps is often cheaper. Mass-market paperback books and newspapers tend to use mechanical papers. Book publishers tend to use acid-free paper, made from fully bleached chemical pulps for hardback and trade paperback books.

Now answer this question: What level of acid is usually found in the paper used by book publishers?

Output: acid-free

Input: Article: Earthworms make a significant contribution to soil fertility. The rear end of the Palolo worm, a marine polychaete that tunnels through coral, detaches in order to spawn at the surface, and the people of Samoa regard these spawning modules as a delicacy. Anglers sometimes find that worms are more effective bait than artificial flies, and worms can be kept for several days in a tin lined with damp moss. Ragworms are commercially important as bait and as food sources for aquaculture, and there have been proposals to farm them in order to reduce over-fishing of their natural populations. Some marine polychaetes' predation on molluscs causes serious losses to fishery and aquaculture operations.

Now answer this question: What type of annelid tunnels through coral?

Output: Palolo worm

Input: Article: From the early 1930s eight countries developed radar, these developments were sufficiently advanced by the late 1930s for development work on sound locating acoustic devices to be generally halted, although equipment was retained. Furthermore, in Britain the volunteer Observer Corps formed in 1925 provided a network of observation posts to report hostile aircraft flying over Britain. Initially radar was used for airspace surveillance to detect approaching hostile aircraft. However, the German Würzburg radar was capable of providing data suitable for controlling AA guns and the British AA No 1 Mk 1 GL radar was designed to be used on AA gun positions.

Now answer this question: When was the Observer Corps formed?

Output:
1925