The whale shark is the largest of all fish and can have the mass of three adult elephants. Suppose that a crane is lifting a whale shark into a tank for delivery
to an aquarium. The crane must exert an unbalanced force of 2.5 x 104 N to
lift the shark from rest. If the shark's acceleration while being lifted equals
1.25 m/s², what is the shark's mass?

m = 20,000 kg

Explanation:

Force,

Acceleration of the shark,

It is required to find the mass of the shark. Let m is the mass. Using second law of motion to find it as follows :

F = ma

Putting the value of F and a to find m

So, the shark's mass is 20,000 kg.

  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

unlike poles attract