Two bicyclists start twenty miles apart and head toward each other, each going at a steady rate of 10 m. p.h. at the same time, a fly that travels at a steady 15 m. p.h. starts from the front wheel of the southbound bicycle and flies to the front wheel of the northbound one, then turns around and flies to the front wheel of the southbound one again, and continues in this manner till he is crushed between the two front wheels. question: what total distance did the fly cover?

15 miles

Explanation:

Speed of both bicyclists is 10 mph

Speed of fly is 15 mph

Time they both will meet at is t

Distance they are apart is 20 miles

Distance = Speed×Time

The time after which they will meet is 1 hour.

The distance traveled by the fly in hour is

The total distance fly covered is 15 miles

  the grams     of oxygen gas   that can be produced     is 20.6   grams of o₂

calculation

2liclo₃ →   2 licl + 3 o₂

step 1:   find the moles of liclo₃

moles = mass÷ molar mass

from periodic table the molar mass of liclo₃ =6.9 +35.5   +(16 x3) =90.4 g/mol

moles=38.7 g÷90.4 g/mol=0.4281   moles

step 2:   use the   mole ratio   to calculate the moles of o2

from equation above, liclo₃: o₂   is 2: 3  

therefore the moles of   o₂=0.4281 moles x3/2 =0.6422   moles

step 3: find mass   of o₂

mass= moles x molar mass

from periodic table the   molar mass of   o₂ = 16 x2= 32 g/mol

mass=0.6422   moles   x   32 g/mol = 20.6 grams of o₂

because growing process had stoped after 4-5 year