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Through-hole manufacture adds to board cost by requiring many holes to be drilled accurately, and limits the available routing area for signal traces on layers immediately below the top layer on multi-layer boards since the holes must pass through all layers to the opposite side. Once surface-mounting came into use, small-sized SMD components were used where possible, with through-hole mounting only of components unsuitably large for surface-mounting due to power requirements or mechanical limitations, or subject to mechanical stress which might damage the PCB.

What type of boards end up with limited routing space in through-hole manufacture?
Answer: multi-layer
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Airports are divided into landside and airside areas. Landside areas include parking lots, public transportation train stations and access roads. Airside areas include all areas accessible to aircraft, including runways, taxiways and aprons. Access from landside areas to airside areas is tightly controlled at most airports. Passengers on commercial flights access airside areas through terminals, where they can purchase tickets, clear security check, or claim luggage and board aircraft through gates. The waiting areas which provide passenger access to aircraft are typically called concourses, although this term is often used interchangeably with terminal.

Airports are divided into what two areas?
Answer: landside and airside
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The Catalan verbal system is basically common to all Western Romance, except that most dialects have replaced the synthetic indicative perfect with a periphrastic form of anar ("to go") + infinitive.

What is the Catalan verbal system common to?
Answer:
all Western Romance