Answer: One canister contains 1.03 Kg of fuel,
Explanation:
The density is defined as the relation between the mass and the volume 
First of all you need to have the same units for volume and density, so:
For the volume,

For the density,

From the density equation we have
, so:

Answer:
a. Springs oscillate with the same frequency
Explanation:
As they both are in the same height at equilibrium, so
weight of ball must be balanced with spring force, that is
k×x=mg
k= stiffness constant of spring
x=distance stretched
g= acceleration due to gravity
so, we can write
k/m=g/x
as the g is a constant and they stretched to same distance x so the g/x term becomes constant and

and k/m is same for both the springs so they will oscillate at the same frequency.
hence option a is correct.
The sound is increased because sound waves are in fact mech. waves which means the that they can't travel through empty space and thus need a medium to travel through
Prior to touching the bar magnet, the magnetic domains in the nail were pointing in random directions. When Taylor touched the nail to the bar magnet the magnetic fields of the magnetic domains aligned and it became a temporary magnet.