a). Water is still H₂O after it freezes.
b). Ice is still H₂O after it melts.
c). Wire is still Cu when it's bent.
d). Paper combines with the O₂ in the air, and turns into
a lot of new compounds when it burns.
If the length of the ruler is 50 cm, the center of gravity cannot be greater than 25 cm.
The given parameters:
- Weight of the ruler = 1 N
<h3>What is center of gravity (CG)?</h3>
- Center of gravity is the point at which the weight of an object is concentrated.
Let the length of the ruler = L
The center of the gravity of the ruler is calculated as follows;

Thus, if the length of the ruler is 50 cm, the center of gravity cannot be greater than 25 cm. This may change if the length of the ruler changes because the center of gravity of uniform ruler depends on the length of the ruler.
Learn more about center of gravity here: brainly.com/question/6765179
Time is being measured in days here so if you want to calculate the rate of increase after one day, substitute 1 for t in your rate equation:
dB/dt = 0.677598 cos(1.232(1))
dB/dt = 0.22