Where the words come from
Why a country may want a weaker currency, how a central bank weakens it (lower interest rates, or creating currency to buy foreign currencies), the effect on exporters' revenue and on aggregate demand, dearer imported inputs shifting short-run aggregate supply left with a possible burst of inflation and recession, and the costs of intervention — Principles of Economics 2e, OpenStax, licensed CC BY 4.0. https://openstax.org/books/principles-economics-2e/pages/29-4-exchange-rate-policies and https://openstax.org/books/principles-economics-2e/pages/32-5-balance-of-trade-concerns. Changes: Condensed from 29.3 (exporters' costs and revenue in two currencies; a weaker rate to stimulate aggregate demand and reduce a recession), 29.4 (the Brazilian example's reasons and two methods, the risk of an inflationary surge, monetary policy tied to the exchange rate) and 32.5 (a lower dollar raising imported input prices, shifting SRAS left, a burst of inflation and possible recession). The French firm, Brazil and the US dollar examples dropped and made general. The first paragraph of block 5 is 2e 32.5, condensed; that block carries the ONS source for its figures. Ours, not 2e: the devaluation and competitive devaluation sentences in block 2; the sentence on how strongly trade volumes respond in block 3; the first paragraph of block 6 on retaliation and currency wars (2e does not discuss retaliation), and "each country still bears the costs". British spelling..
The 18.5 per cent trade-weighted fall in sterling in the year to October 2016, the 12.2 per cent rise in input producer prices, and the 6.9 percentage point contribution of imported products other than crude oil — Additional analysis of the Producer Price Index (PPI) and Consumer Prices Index (CPI): Oct 2016, Office for National Statistics, 15 November 2016, Open Government Licence v3.0. https://www.ons.gov.uk/economy/inflationandpriceindices/articles/additionalanalysisoftheproducerpriceindexppiandconsumerpriceindexcpi/oct2016. Changes: Figures quoted as published; "input PPI" given as producers' input prices; "imported products (excluding crude oil)" given as imported materials other than crude oil. The sentence that the fall followed the EU referendum is ONS's; "a fall no government chose" is ours. Used in the second paragraph of block 5; the first paragraph of that block is condensed from 2e 32.5 and credited in the OpenStax source..
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