Please help fast for question A and B I’d appreciate it

Step-by-step explanation:

a) Since the precision of the ruler is 1 mm, the uncertainty associated with this ruler is +-0.5mm. So the tire tread has a depth of 7.0 mm +- 0.5mm. The amount of tire thread that has worn off is

11.2 mm - (7.0 mm +- 0.5 mm) = 4.2 +- 0.5 mm

b) The tire thread can anywhere between 3.1 mm and 3.5 mm. Since the lower limit has gone below the legal limit of 3.2 mm, it's time to change the tire.

step-by-step explanation:

∆abc has the points a(1, 7), b(-2, 2), and c(4, 2) as its vertices. formed with the point d(1, 2) as its third vertex, then ∆abd is triangle.

the answer is; biodiversity resulting from few ancestors

adaptive radiation occurs when a population is subjected to a large natural environment with spatial ecological variations. the parts of the population in the different ecologies begin to adapt to their local environments. due to non-random mating across the large populations, this causes the different populations from the large population to speciate within their local environments. they, therefore, diverge to different species sharing a common ancestor.