Answer:
The chemical formula for the molecule is 
Explanation :
Molecular formula : It is the chemical formula which depicts the actual number of atoms of each element present in the compound.
Structural formula : It is a formula in which the lines are used between the bonded atoms and the atoms are also shown in the structural formula.
In the structural formula, the lines are used between the atoms.
As per given information of compound we conclude that, there are 4 carbon atoms, 9 hydrogen atoms and 2 oxygen atoms.
Thus, the chemical formula for the given molecule will be, 
The correct expression for the maximum speed of the object during its motion is
.
<h3>
Maximum speed of the object</h3>
The maximum speed of the object is determined using the following formulas;
v(max) = Aω
where;
- A is the amplitude of the motion
- ω is angular speed
The maximum speed of the object can also be obtained from the maximum net force on the object,
F = ma
where;
- F is the maximum net force
- a is the acceleration
- m is mass of the object
F = m(v/t)
mv = Ft
v = Ft/m
Thus, the correct expression for the maximum speed of the object during its motion is
.
Learn more about maximum speed here: brainly.com/question/4931057
Answer
The frequency and the period are 45 cycles/second and 0.023 seconds
Explanation:
The frequency of the engine is given by :

We have, the engine increases its performance from zero to 2700 rpms.
Frequency,

The time period of the engine is given by :
T = f/f
So,

Hence, the required frequency and the period are 45 cycles/second and 0.023 seconds respectively.
I’m pretty sure it’s lean mass but let another guy answer you before you use mine
Heat
You can usually warm something by adding energy. The added energy can be from light, electricity, friction, a chemical reaction, nuclear reaction, or any other kind of energy. When first added to a substance, energy might be concentrated in one atom, but this one will soon bump into others and spread the energy. Eventually, every atom or molecule in the substance will move a bit faster. When the added energy is spread throughout a substance, it is then called heat energy, thermal energy, or, simply heat. All three terms mean the same thing. Heat is a form of energy, so it has the units of energy. In the SI system, this is Joules. Many other units to measure thermal energy are in common use. Calories and BTU's are common heat units.
Temperature
You cannot measure heat directly, but you can detect its effect on a substance. Changes in heat can usually be detected as changes in temperature. Usually, when you add energy to a bunch of atoms they move faster and get hotter. Similarly, if you remove energy from a bunch of atoms, they usually move less and get cooler.