To find an expression for Nikita’s distance during the second part of the race, we first need to determine how much time she spent on each part of the race.
Let:
- \( t \) = time spent in hours during the first part of the race.
- The remaining time for the second part of the race will be \( 0.65 - t \) hours (since the total race time is 0.65 hours).
In the first part of the race, she ran at an average speed of 8.75 km/h:
- The distance for the first part of the race is given by \( \text{distance} = \text{speed} \times \text{time} \). So, the distance for the first part is: \[ \text{Distance}_{\text{first part}} = 8.75t \]
For the second part of the race, her speed dropped to 6 km/h. The time spent in this part is \( 0.65 - t \) hours:
- Therefore, the distance for the second part is: \[ \text{Distance}_{\text{second part}} = 6(0.65 - t) \]
This means that the expression that represents Nikita’s distance for the second part of the race is: \[ 6(0.65 - t) \]
Thus, the answer is 6(0.65 - t).