The key answer of exercise 2

b)

• The idea is a 'piano choir" which is controlled by the keys of a piano.
• Each member of the choir is linked to a different key on the piano.
• Added by the show → Each member of the choir holds a candle-shaped electric light, which is wired to the appropriate key on the piano; when the light goes on, the chorister sings their note.

c)

1. most potential; work out; make of
2. essentially; to
3. happen to
4. worthy of investigation
5. at random
6. give it a go

d)

Sell socks in threes

• Benefits → if a sock got lost in the wash, you'd still have a pair.
• Drawbacks → you could end up with a lot of extra socks that you don't need.

'Democrobus'

• Benefits → could cut down bus journeys because the bus wouldn't stop unnecessarily.
• Drawbacks → time could be wasted discussing/arguing about where the bus should go.

Mini-elephants

• Benefits → they would eat less and cause less damage.
• Drawbacks → there could be many other genetic weaknesses. It could damage eco-systems if they escape.

Food via pipes

• Benefits → would save a lot of time and effort.
• Drawbacks → would have to be a soft or liquid consistency that could go through a pipe.