Answer:
The slope of a position-time graph represents an object’s velocity.
Explanation:
In a position-time graph, the values on the x-axis represent the time, while the values on the y-axis represent the position of the object.
Velocity is defined as the ratio between the displacement of an object and the time taken:

However, we can see that this definition corresponds to the slope of the curve in a position-time graph. In fact:
, the displacement, corresponds to the difference in position, so the difference between the values on the y-axis: 
, the time interval, corresponds to the difference in times, so the difference between the values on the x-axis: 
So, the velocity is

which corresponds to the slope of the curve.
Here's the tool you need. You can't answer the question without this:
"1 watt"
means
"1 joule of energy, generated, used, or moved, every second".
So 60 watts = 60 joules per second
Total energy generated,
used, or moved = (power) x (time).
580 joules = (60 watts) x (time)
Divide each side
by (60 watts): Time = (580 joules) / (60 joules/sec)
= (9 and 2/3) seconds .
The answer is, "B", "Ammonia".
Answer:
m = 35 g
Explanation:
The specific heat of a material can be calculated by the following formula:

where,
C = Specific Heat of Wax = 220 J/g
Q = Amount of Heat Supplied by the Heater = 7700 J
m = mass of wax melted = ?
Therefore,

<u>m = 35 g </u>