Answer: Would be 55% I hope this helps!
123 lb * (0.4536 kg/lb) * 300mg/(kg · day)
= (123 * 0.4536 * 300) mg/day
= 16737.84 mg/day
16737.84 mg/day * 1g/(1000mg)
= 16.73784 g/day
The average speed of Joshua during that time is 2500 m/h.
Explanation:
It is given that Joshua started cycling at 5:15 pm. By 8:09 pm he has covered a distance of 7250 m.
The total time taken by Joshua from 5:15 pm to 8:09 pm is

Dividing we get,

Adding, we have,

Thus, the total time taken by Joshua is 
To determine the average speed we use the formula,

where
and 
Hence, substituting the values we have,

Dividing, we get,

Thus, the average speed of Joshua during that time is 2500 m/h.
I'm not sure what your asking, but if your asking how long it took her, it took her one hour. There is 12 boxes, and each one took her 5 minutes. 12*5 is equal to 60.