What is the measure of the missing angle?
280
78°

2 degrees

Step-by-step explanation:

There is 360 degrees in a circle, triangle, square, and a ton of other shapes, and 280 plus 78 gives you 358 degrees. 360 - 358 equals 2 degrees.

Hope this helps!

- "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."