You have to use the specific heat equation.
Q = cmΔT where Q is the energy, c is specific heat, m is mass, and ΔT is change in temp.
So we can substitute our variables into the equation.
30000J = (390g)(3.9J*g/C)ΔT
Solving for ΔT, we get:
30000J/[(390g)*(3.9J*g/C) = ΔT
ΔT = 19.72386588C
I'm assuming the temperature is C, since it was not specified.
Hope this helps!
Answer:
the magnitude of the work done by the two blocks is the same.
Explanation:
The work done by block a on block b is given by:

where Fa is the force exerted by block a on block b, and d is the distance they cover.
The work done by block b on block a is given by:

where Fb is the force exerted by block b on block a, and d is still the distance they cover.
For Newton's third law, the force exerted by block a on block b is equal to the force exerted by block b on block a, therefore

and so

Answer:
Synthesis reaction
Explanation:
Synthesis reaction: two or more compounds combine to form one.
A + B → C
Decomposition reaction: one compound forms two or more.
C → A + B
Single replacement reaction: an element in one compound is replaced with another element.
AB + C → AC + B
Double replacement reaction: elements in two compounds replace each other.
AB + CD → AC + BD
Gold’s molar mass is about 196 while aluminum is about 27, thus 50cm of gold has more mass