Answer:
The density of block is 2 g/mL.
Explanation:
Density:
Density is equal to the mass of substance divided by its volume.
Units:
SI unit of density is Kg/m3.
Other units are given below,
g/cm3, g/mL , kg/L
Formula:
D=m/v
D= density
m=mass
V=volume
Symbol:
The symbol used for density is called rho. It is represented by ρ. However letter D can also be used to represent the density.
Given data:
mass of block = 12 g
volume = 6 mL
density = ?
Now we will put the values in the formula,
d= m/v
d = 12 g/ 6 mL
d = 2 g/mL
so, the density of block is 2 g/mL .
Answer:
electrons
Explanation:
The photoelectric effect occurs when electrons are emitted from metal when the metal is struck by light of certain frequencies.
Some of the applications of this effect include photomultipliers (which are a key component in spectroscopy instruments) and night vision devices.
Explanation:

<em>According to <u>le ch</u></em><em><u>-</u></em><em><u>atelier'</u></em><em><u>s</u></em><em><u> </u></em><em><u>principle</u> when a chemical reaction at equilibrium subjected to any stress, then the equilibrium shifts in that direction in which effect of stress is reduced.</em>
When we would add more number of carbon in above reaction then rate of forward reaction will increase to attain the equilibrium again.

Choice B I think, because if the temperature decreases the particles move slower due to less kinetic energy, and thus won't collide as frequently.