Answer:
C :She is incorrect because she should have squared each leg length and then found the sum
Answer:
10 calories were burned for each minute of jogging and 10 calories were burned for each minute of cycling.
Step-by-step explanation:
Let be "j" the amount of calories Shelly burned for each minute of jogging and "c" the amount of calories Shelly burned for each minute of cycling.
Set up a system of equations:

You can apply the Elimination method: multiply the first equation by -2, then add the equations and solve for "c":

Now, substitute the value of "c" into any original equation and solve for "j":

From the given, the student may choose from 3 bands, 10 stones, and 25 activity symbols. The number of rings that the students may make from these is the product of these numbers.
number of way = 3 x 10 x 25 = 750
Thus, the answer is letter C. 750.