The purchasing power p of a fixed income of $20000 per year (such as a pension) after t years of 7% inflation can be modeled by p=20000(1.07)^t find the purchasing power after 5 years fin the purchasing power after 20 years

After 5 years: 107,000

After 20 years: 428,000

- "runner b is moving at a slower rate."

- "the graphs shown are graphs of distance(km) against time(min).

the slopes of this graphs are are given by:

slope = (change in y)/(change in x)

= (change in distance)/(change in time)

this is the formula for finding the speed. so, the slope of these graphs represent the speed of the runner.

taking each division in the graph to represent 1 on both axis:

runner a ⇒ speed = (2-0)/(1-0)

= 2/1

= 2 km/min

runner b ⇒ speed = (3-0)/(3-0)

= 3/3

= 1 km/min

this shows that   runner b is moving at a slower rate."