After the last ice age began, the number of plant species in South America changed rapidly.

The relationship between the elapsed time, t, in years, since the ice age began, and the total number of plant species, P(t), is modeled by the following function:

P(t)=30,000,000x(8/9)^t

Every year, the number of plant species (grows/shrinks) by a factor of (blank)

The accompanying normal probability plot was constructed from a sample of 30 readings on tension for mesh screens behind the surface of video display tubes used in computer monitors. does it appear plausible that the tension distribution is normal? the given probability is has a significant downward curve, so it is plausible that the tension distribution is normal. the given probability is has a significant downward curve, so it is not plausible that the tension distribution is normal. the given probability is quite linear, so it is plausible that the tension distribution is normal. the given probability is has a significant upward curve, so it is not plausible that the tension distribution is normal. the given probability is quite linear, so it is not plausible that the tension distribution is normal.