What is predicted about solar energy iCycle 25( )
· Cycle 25 may be stronger thaCycle 24.
· Cycle 25 may be weaker thathe following decades.
· Cycle 25 may be as weak as the period of 1645 to 1715.
· Cycle 25 may be stronger thathe period of 1790 to 1830.

单选题
· The earth is getting warmer and warmer.
· world temperatures have not risen since 1997
· Reduced food production.
· Sunspot numbers in Cycle 24 is less than half those in the 20th century.
· Cycle 25 may be as weak as the period of 1645 to 1715.