Use pythagora's theorem to test if it is a right triangle
c^2 = a^2 + b^2
65^2 = 52^2 + 43^2
4225 = 2704 + 1849
4225 =/= 4553
therefore it is not a right triangle as it does not comply to pythagora's theorem
1.5 minutes = 90 second
The probability density function is

so the probability of interest is


Answer:
What expression are we supposed to be answering this for?
The mean of the track athletes is given by

The mean of the gymnasts is given by

The difference in mean is given by

(rounded to one decimal place)