300cm is the best estimate for a basketball hoop
2 grams
10 grams
3 grams
divide by pi (3.14159) 11.93
A best estimate for the mass of a key is 26 grams.
20 gram
The weight of a standard letter is typically around 5 grams.
0.2 grams
I think 20 grams
1 kg
The best estimate for a pair of sneakers is 1 kilogram.