Marcus is on a train that travels 20 ms and takes 5 seconds to slow to 10 ms. How would Marcus correctly calculate the acceleration?
A
a = (0−20)5 = -4 m/s2

B
a = (10−20)5 = -2 m/s2

C
a = (20−10)5 = 2 m/s2

D
a = (20−0)5 = 4 m/s2

  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

365.25 earth days are in the year of a light year