<span>The ester that is formed by combining propanioc acid with isopropyl alcohol, using heat and an acid catalyst is isopropyl propanoate.</span>
<h2>Answer </h2>
Matter
<u>Explanation </u>
A matter has distinct properties and composition that never vary. The matter is anything which possesses mass and occupies space. The matter has different characteristics and a distribution that does not change from unit to unit. Materials which cannot be disintegrated into simpler materials. Each is made of only one kind of atom in subatomic level. For example, a chair, table, and similar everything that has mass and occupies space is matter.
Answer: 1.8 x 10^1 or the scientific e notation is: 1.8e1
The pressure at the bottom : 19600 N/m²
<h3>Further explanation</h3>
Given
A ground water tank has its height 2m
Required
The pressure at its bottom
Solution
Hydrostatic pressure is the pressure caused by the weight of a liquid.
The weight of a liquid is affected by the force of gravity.
The hydrostatic pressure of a liquid can be formulated:

Ph = hydrostatic pressure (N / m², Pa)
ρ = density of liquid (kg / m³)
g = acceleration due to gravity (m / s²)
h = height / depth of liquid surface (m)
ρ = density of water (kg / m³) = 1000
g = acceleration due to gravity = 9.8 m/ sec²
The pressure

A controlled variable is essentially what is kept the same throughout the whole experiment.