Aball is dropped from the top of a tall building. at the same instant, a second ball is thrown upward from the ground level. when the two balls pass one another, one on the way up, the other on the way down, compare the magnitudes of their acceleration:

a. the acceleration changes during the motion, so you cannot predict the exact value when the two balls pass each other.
b. the acceleration of both balls is the same.
c. the acceleration of the ball thrown upward is greater.
d. the accelerations are in opposite directions.
e. the acceleration of the dropped ball is greater.

B

Explanation:

For the ball dropped From a tall ball building the direction of acceleration is downward and its magnitude is

For the ball thrown upward towards the dropped ball the direction and magnitude of acceleration is same i.e. downwards as gravity always acting downward with constant magnitude.

Thus option B is correct

this allows people to make the best decision or pursue the best option. when alternatives are weighed using their advantages and disadvantages, the option whose disadvantages outweigh the advantages (based on a qualitative or quantitative analysis) are shunned while those whose advantages outweigh their disadvantages are pursued.  

  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