atoms are made of 3 types of sub atomic particles- protons, neutrons and electrons
from these 3 particles, electrons are responsible for participating in chemical bonds. therefore chemical properties of elements are based on the number of electrons present.
valence electrons are the number of electrons in the outermost energy shell that are involved in chemical bonds.
atoms with same number of valence electrons are grouped in to columns called groups.
therefore elements of the same group have same number of valence electrons, hence similar chemical properties.
from the options given
only Be and Mg belong to the same group they both belong to group 2 with 2 valence electrons
therefore Be and Mg have similar chemical properties
answer is
1) Be and Mg
Answer:
Ligands
Explanation:
Ligands are small molecules that transmit signals in between or within cells. Ligands exert their effects by binding to cellular proteins called receptors.
Answer:

Explanation:
The formula for the velocity of the ball is

1. Velocity at time of impact

2. Velocity on rebound
The ball has enough upward velocity to reach a height of 0.86 m.

3. Acceleration

Answer:
The correct answer is A) circulatory
Explanation:
The circulatory system collects metabolic wastes from the blood, which will be eliminated by the kidneys through urine.
The kidneys are responsible for the elimination of waste, acids and excess fluid from the body, maintaining the balance of water, salts and minerals. Blood flows into the kidney through the renal artery.
The reaction: 2H2(g) + O2(g) → 2H2O(g), can be interpreted as: a. 2 moles of hydrogen gas reacts with 1 mole of oxygen gas to produce 2 moles of water.