Donna is running. The number of calories she has burned varies directly with the number of minutes she has run. See the graph below What is the slope of the graph?

How many minutes does donna run per calories burned?

The slope of a graph is the rate of change of the graph.

From the graph, we have the following points.

The slope (m) is calculated as follows:

So, we have:

Hence, the slope of the graph is 10

The number of minutes per calories burned is the inverse of the slope.

Hence, 1 calories is burned in every 0.1 minute.

Read more about slopes and rates at:

link

Slope is 10

5 calories per minute

reduce the friction between its moving parts

step-by-step explanation:

in fact, by reducing the friction between the moving parts of the machine, it is possible to reduce the energy wasted due to this friction; therefore, more input energy is converted into useful work, and this will improve the efficiency of the machine.

correct answers below: