False. Theodore Roosevelt was the youngest.
Answer:
<em>(C) If the composition of a mixture appears uniform no matter where you sample it, is homogeneous; sand on a beach *IS HETEROGENEOUS* because when you look at it up close, you can identify different types of particles, such as sand, shells, and organic matter.</em>
Explanation:
<em>(A) Pure Water is a collection of solely H2O molecules therefore Pure Water is classified as a *Compound*.</em>
<em>(B) Table Salt is NOT a heterogeneous mixture because the particles of salt can't be separated, and it is a *Pure Substance*.</em>
<em>(D) Maple Syrup is a homogeneous mixture because the solutes are fully dissolved and not easily identified. In other words, Maple Syrup is uniform throughout.</em>
<em>-Hope this helps!</em>
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Answer:
Efficiency = 80%
Explanation:
Given the following data;
Work output = 240 N
Work Input = 300 N
To find the mechanical efficiency of a machine;
Substituting into the equation, we have;

Efficiency = 80%
Therefore, the mechanical efficiency of the machine is 80 percent.
Answer:
a. 
b.
must be the minimum magnitude of deceleration to avoid hitting the leading car before stopping
c.
is the time taken to stop after braking
Explanation:
Given:
- speed of leading car,

- speed of lagging car,

- distance between the cars,

- deceleration of the leading car after braking,

a.
Time taken by the car to stop:

where:
, final velocity after braking
time taken


b.
using the eq. of motion for the given condition:

where:
final velocity of the chasing car after braking = 0
acceleration of the chasing car after braking

must be the minimum magnitude of deceleration to avoid hitting the leading car before stopping
c.
time taken by the chasing car to stop:


is the time taken to stop after braking