A resting object starts accelerating down a straight track. It accelerates at 2 m/s squared for 6.5 seconds, then and 8 m/s squared for 9.25 seconds, and finally at 4 m/s squared for 4.75 seconds. What is the objects final velocity

106 m /s

Explanation:

v = u + at

v is final , u is initial , a is acceleration and t is time .

velocity after initial 6.5 s

v = 0 + 2 x 6.5 = 13 m /s

This becomes initial velocity for 9.25 s stretch .

velocity after next 9.5 s

v = 13+ 8 x 9.25

= 87 m /s

This becomes initial velocity for 4.75 s stretch .

Final velocity after next 4.75 s

v = 87 + 4 x 4.75

= 106 m /s

  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

i believe the answer would be:

d. violin, clarinet, french horn, and tuba