Exercise 3 solution

8 C: probably not flying freely. The article says bees are immobile below 7 to 10 C; 8 C is inside that band, so little or no flying (the exact threshold is not given more precisely).
23 C: yes. This is inside the optimal foraging range of 22 to 25 C.
40 C: activity slows, because it is above 38 C, but bees can tolerate up to 50 C for short periods, so some activity is still expected.