Answer:
It will take 58 seconds
Step-by-step explanation:
If you have 1 kg of water in the jar, half of it will be 0.5 kg.
To vaporize half of the water (0.500 kg) the energy supply needed is

If the stove is supplying 20 kJ/s, the time its needed is

It will last at least 58 seconds to vaporize half of the water.
We can use a system of equations to solve this.
Length 1 = x
Length 2 = y
Set up the system.
2x+2y=38
x+1=4y
Isolate the variable on one equation.
x=4y-1
Substitute that into the other equation.
2(4y-1)+2y=38
Solve.
8y-2+2y=38
10y=40
y=4
Substitute back into other equation.
x=4(4)-1=16-1=15
The lengths are 15 cm and 4 cm.
Hope this helps!
Here is a video that can also explain this question
Answer:
I think its C!! but not sure