Convert the weight of the Olympic rings to kilograms.

USA swimmer's time: $4 \text{ minutes } 11.07 \text{ seconds} = (4 \times 60) + 11.07 = 240 + 11.07 = 251.07 \text{ seconds}$.
Olympic record: $4 \text{ minutes } 3.84 \text{ seconds} = (4 \times 60) + 3.84 = 240 + 3.84 = 243.84 \text{ seconds}$.

The USA swimmer was $\boxed{\text{7.23 seconds}}$ slower than the Olympic record holder.

Question 2.5.2:
Calculate Arienne Titmus's average speed, in km/h during this final race.

Distance = $400 \text{ m}$.
Time = $3 \text{ minutes } 57 \text{ seconds}$.

Time in seconds = $(3 \times 60) + 57 = 180 + 57 = 237 \text{ seconds}$.
Time in hours = $\frac{237}{3600} \text{ hours} \approx 0.065833... \text{ hours}$.
Rounding to three decimal places: $0.066 \text{ hours}$.

Distance = $400 \text{ m} = \frac{400}{1000} \text{ km} = 0.4 \text{ km}$.

Her average speed was $\boxed{\text{6.061 km/h}}$.

Question 3.1.1:
Convert the weight of the Olympic rings to kilograms.

Total weight = $30 \text{ tonnes}$.
Conversion factor: $1 \text{ ton} = 1000 \text{ kg}$.

The weight of the Olympic rings is $\boxed{\text{30000 kg}}$.

Question 3.1.2:
Show by means of calculations whether the tour guide's statement is correct.

Given diameter ($d$) = $9 \text{ m}$ and $\pi = 3.142$.

Rounding to two decimal places: $28.28 \text{ m}$.

There are 5 rings.

Height of Eiffel Tower = $330 \text{ m}$.

The tour guide claims the total distance is less than 40% of the height.
Total distance = $141.40 \text{ m}$.
40% of height = $132 \text{ m}$.
Since $141.40 \text{ m} > 132 \text{ m}$, the total distance is not less than 40% of the Eiffel Tower's height.

The tour guide's statement is $\boxed{\text{incorrect}}$.

I still need the text for questions 1.1, 1.2, 1.3, 1.4, 1.6, and Annexure B for other parts of Question 2.