Hello!
To solve this problem you need to use the following equation for heat transfer to calculate the heat added (Q) and substitute in this equation the values for specific heat (c), mass (m) and temperature difference (ΔT). The following equation describes the heat needed to raise the temperature of a given object:

:
So, to heat the cafeteria fork made of iron with a mass of 20 grams from 25 °C to 75°C, you'll need
121 cal of heat energy.
I thinks it's B. Molecular Receptor, but I am not sure.
The correct question with the options would be:
During which part of the cell cycle is DNA polymerase most active?
a. G1 phase of interphase
b. mitosis
c. S phase of interphase
d. G2 phase of interphase
e. cytokinesis
The correct answer is c. S phase of interphase.
The replication of the entire genome or the whole DNA occurs during the S-phase or also called synthesis phase. Therefore, the enzyme is DNA polymerase which carries out the replication of DNA shows its maximum activity. The DNA polymerase is active in various cell cycle checkpoints to detect the DNA damage but the repair action of DNA polymerase involves only a small region of DNA as compared to the whole genome during the S-phase.
A soil can be low in ammonium and potassium ions because of increased acidity of the soil. The acidity is caused by hidrogen (H) and Al (alluminuim) ions. There few causes: acid rain, nitrate leaching, rainfall, decompositions of organic matter (leaves, corps etc) due to microorganism activity.