Black hole I think that is right
The formula for energy or enthalpy is:
E = m Cp (T2 – T1)
where E is energy = 63 J, m is mass = 8 g, Cp is the
specific heat, T is temperature
63 J = 8 g * Cp * (340 K – 314 K)
<span>Cp = 0.3 J / g K</span>
If you mean the number of Significant Figures/Digits in 23.45, it would be 4. This is because every single non-zero digit is counted as a significant figure