Change minutes to hrs, divide by 60:
30 min = .50 hrs
45 min = .75 hrs
12 min = .20 hrs
----------------
total + 1.45 hrs, total travel time
:
let a = average speed for the trip
:
Write a dist equation, dist = speed * time
:
80(.5) + 100(.20) + 40(.75) = 1.45a
40 + 20 + 30 = 1.45a
90 = 1.45a
a =
a = 62.069 km/h, for the entire trip
and
90 km is the total distance
Of the materials listed wood is the best insulator. It would be the least hot if exposed to similar temperatures.
Answer:
Explanation:
The change in kinetic energy will be simply the difference between the final and initial kinetic energies: 
We know that the formula for the kinetic energy for an object is:
where <em>m </em>is the mass of the object and <em>v</em> its velocity.
For our case then we have:
Which for our values is:
Evaporation is the process by which water changes from a liquid to a gas or vapor. Evaporation is the primary pathway that water moves from the liquid state back into the water cycle as atmospheric water vapor. Studies have shown that the oceans, seas, lakes, and rivers provide nearly 90 percent of the moisture in the atmosphere via evaporation, with the remaining 10 percent being contributed by plant transpiration.
1). Take a sample of the substance. The sample should be the largest
possible that will allow it to be be easily handled and the following steps
to be performed with it.
(The density doesn't depend on the size of the sample, and every sample
of the same substance has the same density. But using a larger sample
can improve the accuracy of the measurements you make, and therefore
improve the accuracy of the density you derive for the substance.)
2). Ask or measure the mass of the sample.
3). Ask or measure the volume of the sample.
4). Divide the mass by the volume. Their quotient is the density
of the substance.
