The acceleration of the object if the net force is decreased = 0.13 m/s²
<h3>Further explanation</h3>
Given
A net force of 0.8 N acting on a 1.5-kg mass.
The net force is decreased to 0.2 N
Required
The acceleration of the object if the net force is decreased
Solution
Newton's 2nd law :

The mass used in state 1 and 2 remains the same, at 1.5 kg
ΣF=0.8 N
m=1.5 kg
The acceleration, a:

ΣF=0.2 N
m=1.5 kg
The acceleration, a:

Answer:
(B) The number of protons - only the number of protons in the nucleus determines the element - mass and neutrons can vary for the same element
Answer:
Photoelectric effect, phenomenon in which electrically charged particles are released from or within a material when it absorbs electromagnetic radiation. The effect is often defined as the ejection of electrons from a metal plate when light falls on it.
Explanation: