Scientists have observed that the average sunspots have increased in the last 50 years. which of these statements best describes an effect of this increase in sunspots?

a) earth's temperature has become cooler.
b) earth's temperature has not changed over time.
c) earth's temperature has become warmer.
d) earth's temperature has reduced by fifty times.

Consider a production line with five stations. station 1 can produce a unit in 9 minutes. station 2 can produce a unit in 10 minutes. station 3 has two identical machines, each of which can process a unit in 12 minutes (each unit only needs to be processed on one of the two machines. station 4 can produce a unit in 5 minutes. station 5 can produce a unit in 8 minutes. which station is the bottleneck station?