Answer:
ΔH°comb=-5899.5 kJ/mol
Explanation:
First, consider the energy balance:
Where 
is the calorimeter mass and 
is the number of moles of the samples; 
is the combustion enthalpy. The energy balance says that the energy that the reaction release is employed in rise the temperature of the calorimeter, which is designed to be adiabatic, so it is suppose that the total energy is employed rising the calorimeter temperature.
The product 
is the heat capacity, so the balance equation is:
So, the enthalpy of combustion can be calculated:
I will be happy to solve any doubt you have.
The magnitude of your displacement can be equal to the distance you covered, or it can be less than the distance you covered. But it can never be greater than the distance you covered.
This is because displacement is a straight line, whereas distance can be a straight line, a squiggly line, a zig-zag line, a line with loops in it, a line with a bunch of back-and-forths in it, or any other kind of line.
The straight line is always the shortest path between two points.
The answer is static friction. This is the friction that involves objects that do not move.
The gravitational force between two objects is given by
where
G is the gravitational constant
m1 and m2 are the masses of the two objects
r is the separation between the two objects
In this problem,
,
and
, therefore the gravitational force between the two objects is
